HELP! Im looking for a game like CIV 6 where the point is to go to war

There is another comment that says this, but for clarity there is a franchise called "Total War" that has multiple editions which is exactly what you are looking for. They also have the ability to control the specific battles on the field like an RTS or you can play it with the battles operating like Civ. I personally really like the Total War Warhammer 3 edition (but I'm a Warhammer fan).
- I will throw in another vouch for this series. It is exactly what you're looking for. I haven't played any of the more recent entries but I've heard they've been received very well. Total War: Rome 2 is a classic, but for something more modern I've heard only good things about Three Kingdoms, though I haven't played that one personally.
- Op, this is it. The franchise has been around for decades and covers many historical eras. Recently they got into fantasy and did well with it, though personally I prefer the historical titles with the dynamic dueling.
  Like Dr_Nik said, battles are either RTS style that you can choose to control, let ai take over and observe the battle instead, or you can autoresolve and skip a battle entirely. The overall gameplay is similar across each game, but the mechanics and ai behavior vary wildly across titles. If you don't like one game, pick up another and you'll probably love it
- Agreed with this. Started in the CIV world with 5, then a buddy introduced me to Rome:Total War and it was like finding crack. I still like to take over all of Europe at some point once a year.
  Just a heads up OP, the games are limited to regions of the world, it's never the full globe.

Domination victory is literally one of the victoru conditions of Civ 6. You're allowed to go full steamroll and go to war with everyone. Some of the civs are focused on going to war and expanding quickly through warfare like the Aztecs. Just don't be surprised when you keep attacking other civs and the other players use the other diplomatic strategies to their advantage.
I'm Civ it's also important to know how the other players perceive you and how to manipulate that perception to your advantage. Manufacture Casus Belli, poke and prod until others make the first attack and you "defend" yourself by taking their cities. You'll be less of a warmonger.

I mean… it CAN be the point of the game. Wouldn’t you expect some pushback if you decided domination was your path to victory?
- I want a game where everyone is out for themselves, and if a nation gets wiped out in the process, so be it.
  
  Go into politics.
  
  This makes no tactical sense. If a player is losing, they will do everything to stop it. Alliances are part of it.
  
  I mean, what’s stopping you from playing Civ that way? I think a lot of players do.

Try Stellaris. It's similar gameplay, but it's realtime and the space battles you can get yourself into can be truly epic.
- As someone who just spent the last 30 years in a huge galaxy spanning war to try and seize Terminal Egress from a 7 strong federation and then had a 10x Unbidden appear in Fen Habbanis that produced 85% of my alloys crippling my ability to fight them off for 20 years. I second this recommendation.

Total war is fantastic and fits the bill.

Warhammer 40,000: Gladius - Relics of War.
In the grim darkness of the far future there is only war.
- I thought I would get a few minutes in before a meeting and I missed it completely. Gladius definitely scratches the itch!
  
  Go and warmonger your blood thirsty heart out. Remember, the only good xenos is a dead xenos.

Maybe Hearts of Iron or Stellaris?
- Stellaris Looks like a good call! But theres a million DLCs and the whole thing costs over £200 and I dont know which ones I need
  
  You need none. They release free content together with every DLC too. Also you can get the subscription for a month and cancel immediately if you want to try all of them.
  
  Start with the base game and take it from there. You don't "need" any DLC
  
  You say that as if it wasn't true for civ 6 as well haha

Any total war game really, you also get the fun of actually commanding an army.

Probably the Total War series is up your alley.. sounds exactly like what you did in Civ 6.. you amass a giant army and go around putting everyone in their place.. and often enough someone shows up to put you in yours.. also for the combat you can just select auto and it will just do the battle for you, ORRRRR you can manually do the combat and control each of your units (cavalry, swordsman, officers.. etc) it’s really pretty neat if not a little overwhelming at points.

I don’t understand. You want a game where you can go to war with countries that won’t declare war on you?
- Exactly! Everyone starts hitting each other with sticks, until eventually you wipe out all life.
  
  Haven't played any civ in ages but there should (could) be a setting "Only War" or something similar that makes everyone hostile to eachother. Or there may be a mod to the same effect.

Isn't that the point of the Ghandi playthrough?

You might like Age of Empires (2 or 4)

CIV 5 is better than CIV 6. You can be a war monger but the effects are less than 6.
For pure carnage, CIV 4 Beyond The Sword.

Crusader Kings 3 is my favourite game like this. I wouldn't say the point is to go to war, but it's a pretty big part of the experience. Has a lot of DLC but you can definitely have a ton of fun with the base game if you don't want to commit to that.
- I second this, it‘s not 4x but it might just be what OP is looking for regardless. Paradox‘ DLC policy hell is something to be aware of before jumping in without a doubt

Diplomacy Is Not An Option, maybe?

Wait, that's not how you're supposed to play Civ? Is there any other way?!

The game "Humankind" plays very similar to civ 6, might be better to compare it to being inbetween civ 6 and 7. But it has a much more tactical combat system.
- I found humankind to be very difficult to go the domination path, but I haven't played since close to release.
  It was very prohibitive to take direct control of conquered cities as the cost seemed exponential, and you had to constantly declare peace and then go right back to war or something if I remember correctly. It seemed like a silly system

Real life

There was an old computer game Warlords. It was turned based and you can even play it online nowadays.
Warlords

Age of empires 2

Hearts of Iron IV. It’s a grand strategy but War is the whole point.

It works as in real life.
If you want a world where everyone welcome your power, that can only be achieved economically and with endocrinement as religion, media...