from 1-50 you are drip fed skills every 5 levels, you start with 1 skill.
You have an autoattack which is pretty meaningless in the grand scheme of things, say you have an axe that deals 100 dmg, and it has a delay of 3.5 (pretty typical for 2h axe that warrior uses).
So you deal 100 dmg every 3.5 seconds.
To start you have 1 button you can press, heavy strike, which deals 150 damage. Every 2.5s (GCD) you deal 150 dmg, every 3.5s you autoattack for 100.
Then after a few levels you get a 2nd button you can press, maim. It deals 130 dmg, unless you use it after heavy strike, in which case it deals 250. (and "after" is fucking forgiving, like 24s to to use it, and it doesn't have to be on the same target, it's not a debuff on a mob, it isn't a combo point you are building or anything)
So to start, you have to "decide" what to do. press 1 to deal 150, or press 2 to deal 130. This isn't a choice, you always press 1.
Next GCD, you "decide" what to do. press 1 to deal 150, or press 2 to deal 250. This isn't a choice, you always press 2. and repeat.
so you press 1,2,1,2, etc.
There's no resource to manage or think about, mobs don't actually deal damage to you. I mean i guess they do but you are never at risk of dying, you will never drop below 90% health and you seem to have the same insane health regen in combat as well as out, there's no downtime to manage. There's telegraphs but they are extremely forgiving, you can type a sonnet in the time you have to move out of the aoe. You do get a 30s cooldown stun and an interrupt but mobs you can use interrupt on are a handful of boss abilities sprinkled through 50 levels. Stun you can use on trash to avoid having to avoid their aoes, ie if you are lazy.
Around the mid 20s you gain a 3rd skill. It deals 120 dmg, unless you use it after Maim, in which case it deals 380 dmg and heals you.
So again:
press 1 to deal 150, 2 to deal 130, or 3 to deal 120. You always press 1.
then press 1 to deal 150, 2 to deal 250, or 3 to deal 120. You always press 2.
then press 1 to deal 150, 2 to deal 130, or 3 to deal 380 and heal yourself. You always press 3.
And that's combat. You also get an AOE "rotation" slowly drip fed to you which is identical to the above except no 3, just 1,2.
Mid 30s you get a resource, which you build by pressing 2,3 that lets you deal 330 dmg that doesn't interfere with the 1,2,3 "rotation". at level 50 you gain an AOE version of this resource consumer.
And finally, at level 50, you gain your first actual choice in combat:
Storm's Eye, deals 120 unless used after Maim(2), in which case it deals 380 and gives you a 10% dmg buff.
So now your options are:
press 1 to deal 150, 2 to deal 130, 3 to deal 120, or 4 to deal 120. You always press 1.
then press 1 to deal 150, 2 to deal 250, 3 to deal 120, or 4 to deal 120. You always press 2.
then press 1 to deal 150, 2 to deal 130, 3 to deal 380 and heal yourself, or 4 to deal 380 and give yourself 10% dmg buff. See what it did there? You now have a choice. Do you need the heal(3) or do you need the buff(4)? it's also slightly more complex! 3 gives you 20 resource, while 4 only gives you 10. you start to have to think about managing that resource you were given 20 levels earlier!
mind you this buff you also gain from the AOE rotation and it stacks for up to 60s duration, so 90% of the time you already have the buff from AOEing the trash and your health isn't 100% from clearing all the trash, so you typically still choose 3 mainly and the periodically use 4 to refresh your buff, but it's nice to have the option.