Warrior Fury

I loved the warrior class in WoW it was one of the easiest and most fulfilling classes I’ve played but something happened in the meantime, after I dinged level 120 I would remain behind in the damage meeter list, I had good items, for some reason the character checklist doesn’t show me right now the item level that I have I think blizzard dispatched it. So I was leveling as a fury warrior and in my dungeon quests I had no problem doing a lot of damage to the NPCs in the leveling process but when I reached the top my damage was pretty low and I didn’t understand that most of the raid/team members were doing good even other warriors but my combo skills were that bad? I searched for tactics on the internet and rotations along the way to see how to improve my damage-dealing abilities. I have a 120 Tauren warrior at the moment so I max level but I need to do more damage in the raid/dungeon encounters to better have a tight grip at what I’m doing right here.
While I was leveling I didn’t like tanking, especially warrior tanking I thought they were pretty boring, I prefer DK tanking or paladin, but Warrior it’s pretty hard to gather all the mobs especially if they are more in the zone. So in my dungeon quests I usually went for fury it was my favorite specialization as a warrior dealing damage with two two-handed weapons was good looking and good for dealing damage to the NPCs, while leveling I was always in the top at damage meeters but as soon as I dinged 120 and went to raids that damage dropped drastically, I was thinking maybe because of all the high item equipped team members, it I wasn’t really that good at making combo moves with buttons the rotation at max level is not that easy it’s really complex and has many possibilities, besides the fact that while leveling you only have a few possibilities of combo points at max level when you have all the spells you need for your class it really gets interesting.
But what I do not understand is the fact that I don’t know what I’m doing wrong is it that I don’t have the necessary gear for the sustained damage dealing or I don’t know how to press the combo moves right.

If I would be a good damage dealing warrior at the max level I would probably play it more but as far as I am now in the thing I see that I must do maybe some World Quests and get more accommodated to the class than I already am before I could raid properly.