There are a couple of basics to go over Let's get to it:
1) Your build. The question here is what you want to do - follow some guides and the established meta, or do your "own thing". I'm always kind of looking for a middle way, reading existing guides, but do that with a critical thinking cap, asking myself "is this really what I want to do, how can I adjust this to my personal preference"? It also depends very much on the gear you have. And that last point is very important - your build needs to match the pieces you're wearing, and right now it's more a mixture of random things that don't really synergize well
Why are you using Furious Charge? Many people are using this, either to proc the Focus and Restraint rings' set combo, or for quick movement. In any case, the by far most preferable rune for Furious Charge is "Merciless Assault" as it gives you a charge back if you charge into 5+ enemies. However, when not running Focus and Restraint this skill is not the most useful one.
Why are you using Weapon Throw? As a generator? You have already many existing spells that you can turn into a generator (Furious Charge with Merciless Assault, though it only works on great density maps; Whirlwind with Wind Shear; Call of the Ancients with Ancient's Fury). Also, you have only one real "resource spender" in your build (Whirlwind), but that one requires you to keep it clicked as it's a channeling spell - so it really doesn't synergize well with a classical generator.
Ignore Pain - Iron Hide. Your belt has only 4 seconds as secondary roll, you have literally no cooldown reduction on gear - so Ignore Pain doesn't really have a high uptime. If you have survivabiltiy issues you can remedy this in other ways (I'll get to that later).
So... criticizing so many spells - what else could you do? Well, for a start, I think you want to use War Cry. War Cry (best runes are Veteran's Call or Impunity) gives you an insane toughness boost. Veteran's Call might give you more sheet toughness, but it's a dodge mechanic: dodge mean you either take no damage from a hit, or the full damage. Impunity will give you a more constant damage reduction, you will see less "spikes". It's your pick! Also, War Cry gives some extra fury, which is always nice.
Battle Rage. It's another great buff, you just need to get used to pressing it approx. every 2 minutes. Many of the runes are useful, although the last one (Bloodshed) is only a good choice if you have really high crit chance (50%-60% or more), so don't be fooled by the fact that almost everyone uses it. Many people copy builds without understanding why, always keep that in mind
Threatening Shout is another great spell that can give you some more fury, more survivability, and more damage, depending on the rune. You should try that out.
Many people use Sprint (if they feel too slow) or other spells, on my HC barb I like to use Overpower sometimes. It all comes down to preference and playstyle. Try out some of the spells and see what works for you.
Passives: Juggernaut is not really a good passive, and it's totally useless since you will have permanent Wrath of the Berserker (thanks to your Immortal King's 6 piece bonus), so you're immune to crowd control effects. It's pointless here
Similarly, Animosity and Unforgiving do not offer a good bang for your buck.
If you need survivability, consider these passives: Superstition, Bloodthirst, Tough as Nails. If you don't need more survivability, you can take the damage passives: Rampage, Brawler, Weapon Master (in addition to the good damage passive Ruthless which you already have).
In solo Greater Rifts it is probably not a bad idea to use Nerves of Steel; if you die right after casting your ancients you will have a looong cooldown.
2) Item composition.
Your items are a bit weird, since you are using the BK weapons (which are awesome for Whirlwind) but the Immortal King's set (which has nothing to do with Whirlwind). Whirlwind is a popular build, but almost exclusively because everyone uses the 6 piece "Wastes" set which, if you look at it, turns your Dust Devils into crazy damage dealers. 2500%!!! That's a bit more than the 340%-400% the Whirlwind runes have without the set ;-)
This is not to say that Whirlwind without Wastes doesn't work, but you'll only do one eighth (!) of the damage other WW barbs with the set will deal. A good thing to pair up with the Immortal King set, which you are wearing, is usually one of the hard-hitting spells - especially Seismic Slam or Hammer of the Ancients, the latter being the most popular build right now. You also want a two-handed weapon then that hits really hard with every smash ;-) Do you have either of the bracers (HotA/SS) and weapons (HotA/SS)? Then you could try one of these spells. You might need a bit more fury then, but if you're not playing WW anymore you can also take on a classical generator to deal with that - but Ancient's Fury, which you gain through your shoulders, should really be fine for that already.
In general, you want to look at your orange legendary item bonuses and set bonuses (like you did for the 6 piece Immortal King's set!) and combine some things that sound cool, especially when it comes to your main damage sources.
In jewelry you always want a socket, and you always want to add a legendary gem. Always, for any class, ever. Preferably you want to unlock as many rank 25 abilities as possible, as you did on your Bane of the Powerful. Note that Bane of the Powerful is only useful if you kill an elite pack while the last buff is still up, which means you encounter an elite pack about every 40 seconds or so. When you're "pushing it" in Greater Rifts, and they take you more than 6-8 minutes to complete, you will most likely be better off using other gems.
Again, there are two great choices for survivability that can make it much easier for you to survive: Esoteric Alteration and Molten Wildebeest. Especially Esoteric is a gem that you should level up once you get it, it's useful from the start and will always be helpful.
There are also lots of choices for offensive gems: Bane of the Trapped is basically the go-to gem that everyone uses that deals damage. Taeguk is great when you're constantly spending resource (e.g., for a Whirlwind spec) and even toughness once it's at rank 25 - but it can be tedious to "keep it up" sometimes. I'd suggest you keep this for later, level it up when you have time - at around rank 30-40 Taeguk becomes better than many other gems. Gogok is also a nice gem *if and only if* you need attack speed and CDR. In your case that's not really true, but it might be a good starter gem and it's not a bad idea to have one at rank 25 whenever you need it. Bane of the Stricken is a must-have if fights last longer. It's useless when mobs die in less than 5-10 seconds, but whenever you're pushing Greater Rifts and the rift guardian takes 1-2 minutes to kill, Bane of the Stricken is golden. Last but not least, should you ever go full Whirlwind, Pain Enhancer is hands down the best gem ONCE it's at rank 25. It doesn't need to be higher, but it's rather useless before rank 25.
There are other gems that might sound useful, but those are basically the gems that are used by 99% of the playerbase and are considered to be best for barbarians.
Oh and another thing: You want an emerald in your weapon, not a ruby
4) Item stat choice
The most important damage stat is critical hit chance and critical hit damage. You want this on every piece possible: On amulet you need both stats. On rings and gloves you want both if possible, but CHC (critical hit chance) is more important by far. On helmet and bracers you want CHC as well. If you want to find a good balance between CHC and CHD and calculate how much damage you gain, there's a calculator in my signature.
You made some rather odd re-roll choices, if I may say so For example, your gloves have two rather useless stats (resource cost reduction and life on hit). If you lack resource, again.... I mentioned this above what to do And life on hit is not that good for barbarians, as you rather want life per fury spent. Thorns, the secondary you rolled, is completely useless. It hurts to tell you but: you want to get new gloves, they're really really bad. If you have an Immortal King's weapon or belt use that and use any other gloves you can get your hands on; best ones would be strength, vitality, critical hit chance, and critical hit damage.
In general, always make sure the primary stats are "correct" before re-rolling the secondary stats. First, you want the damage stats that I mentioned before (strength on every piece, CHC, CHD); then you want vitality and all resist on as many pieces as possible. Note that you can only roll all resist if the item doesn't have a single resist. Life % is also good for barbarians, but you need to make sure you have high enough vitality rolls on your gear. And always socket all your jewelry and weapons You can't do that on your second BK weapon (and should not use a gift on that, only use Ramaladnis Gifts on well-rolled ancient weapons).
Thank you, thank you I read what you said about the "Wastes" set & I have that 5/6 + the ring of grandeur cube so now I have HOTA that don't die & a full set of "Wastes" on & I smoked through a lvl 30 Grift with NP!
- A Hellfire Ring is good for XP, but not for pushing GRs. Do you have another, better ring, with socket/str/CHC/CHD (in this order)? Also, the best rings by far are Focus and Restraint, followed by Convention of Elements, Stone of Jordan, and Ring or Royal Grandeur (so you can take an additional off-set piece). Skull Grasp is useless because its damage bonus is additive, not multiplicative; most people use Convention of Elements in the Cube, so it's your right choice.
- Get rid of life regeneration and life on hit; you have life per fury spent and Blood Funnel for that. For Blood Funnel, you want to have as much HP as possible, so make sure to have vitality on every piece, and life% (but only second priority). Specifically: shoulders => CDR or life%, chest => life%, belt => get a new one (Goldwrap is 1000% useless in GRs) with str, vit, all resist, life%, pants => vitality.
- Why did you re-roll main stat on your gloves? The armor is completely useless since you're a strength class and have plenty of armor. As mentioned above, you want CHD and vitality on gloves in addition to CHC and strength that always roll.
- Try to get other bracers, Nemesis aren't really good for a WW barb as your strength is not to kill elites, so you want LESS elites, not more. You really want bracers with strength, CHC, vitality, and physical damage (in this priority).
- Your offhand is AMAZING. I hope you didn't touch it yet? Wait for a gift, re-roll the socket to damage%, and put a gift on it. Also, swap your weapons, and put an emerald in BOTH - again, you're not an elite killer, plus the diamond is inferior to the emerald.
- Also try to get a new helmet, with str/socket/WW damage and either vitality or CHC, the life per hit is kinda useless.
You're on the right track, you just need more damage to get higher (which is mainly your wrong weapon gem, missing CHD on gloves, missing CHC/low CHD on the second ring, no Focus+Restraint which are a 125% damage boost).