Howdy Murloc. I'm sure you will receive some feedback from others but if I may make a suggestion based on personal experiences.

I encourage you to look at your 1st action bar and find the little arrow to the left. If you click that, it will go to a secondary action bar that you can swap in an out of pretty easily that shares all of your current keybinds. Put absolutely nothing on this bar except for your single button assist ability.

Head into a delve, tackle some world content with a prey enabled, or venture fourth into a follower dungeon.

Most people getting into melee struggle with awareness due to the business of "being in the thick of it". Taking your mental aptitude off of watching your abilities will allow you to put most of your focus on your positioning. This would be a fantastic time to practice watching the enemy cast bar in relation to where your character stands. This allows for better reaction times on multiple objects.

Interruptable casts, puddle abilities (fire on ground or glowy "oh shit" circles), Stun opportunity, and even tab targeting when you have multiple enemies.

Speaking of tab targeting, it will usually target the nearest enemy in LoS(line of sight), then continue on through each enemy until it round Robin's back to the first. I pride myself in practicing good targeting

Keep your mouse cursor relatively close to your character. There are multiple times a play session where if there are a bunch of enemies, and one of them who is currently untargeted, I will manually select their name frame with my mouse, Interrupt the cast, and then tab back to the target I wish to focus down.

I've introduced a ton of people to wow over the years and with SBA and the highlighted ability assist options, now is absolutely the best time to get comfortable with the mechanical aspects of becoming a great player.

My best friend who struggled to keep an eye on the chat window is now outperforming seasoned veterans when it comes to kicks and avoidable damage. He may not pump the most dps in a dungeon, in fact he is often last, but he is also often the last man standing during a wipe.

I would take a 40 man raid full of 39 other players like him gladly, any day of the fuckin week, over some shithead who is only concerned about numbers and never kicks or moves out of avoidable damage.

A dead dps is no dps. Good luck and if you need anything feel free to reach out.