About to start this, what am I in for

what is it then?

It's fun. A lot of different army choices and mechanics. The gameplay is fairly shallow, but progression is generally enjoyable.

Warhammer, a sort of unrestricted warfare but it's the second part.

AI bullshit. Micromanagement. Boring maps.

well, you won't be playing an RTS so there's that

tbs with rtt battles

Rts? This is archer gymnastics the game

spearman/archer simulator with fireworks

>a game made after Total War stopped being good
Elaborate

As others said, it's more rtt than rts. But you never played an rts before, so it doesn't matter much.
A lot of decisions will be in the turn based strategy part of the game. Economy is generally important to consider, as well as troop composition and leveling your leadership.
Actual combat depends on using your army to take advantage of their strengths, gimmicks, and the terrain over the enemy.
In simplest terms, build effective walls of melee units to stop the enemy army while your ranged and artillery pelt them from relative safety. Cavalry let's you out maneuver and do hit and runs on weaker enemy units, or pincer their frontline fighting your melee wall.
Every faction plays different, some more drastically than others. If you just have base TW2, I recommend High Elves just to get a feel for things, as they have closest to traditional line warfare tactics and overall strategy.

okay thanks user and the others

You're up for kino of incredibly high order
Pick Tyrion if you want a safe start and strong troops. Pick Lizards if you want retard strength infantry and decent skirmishers. Avoid the skaven because skaven are for faggot