AI enemy aircraft

I’m trying to make a top-down game based around aircraft battles, to do that, I need to code the enemies
What the Ai needs to do is move behind the player and fire. I can’t use path finding because it needs to be constantly moving, I tried making a new behavior but A) I couldn’t figure out how, and B) I still don’t know how to get it to work how it should in the first place
I made a similar game previously where all I really did was make them rotate towards a position no matter what, but I want to know if there is a better/more advanced way to do it

My 1st idea
If enemy Y position is less than player Y position + 100 (meaning current player Y position + 100 pixels down from player so number should be adjusted)

You simply add force or move or whatever enemy aircraft to some position
For example to Player Y position +100