Dude, just a word of encouragement... I've been flying DCS since JAN 2020. AAR almost made me quit entirely. Literally spent weeks (if not months) dedicating all of my DCS time to trying to nail refueling. One day it just clicked... and I wasn't sure why I could all of a sudden do it until about a year later when I joined an online group and started trying to fly formation with other guys. d0ppler's advice is spot on. focus on a que on the tanker, keep the hose in your periphery, but don't focus on it. Take it slow, and when you feel the need to make a correction, input half of what you feel like you need to do. Patience is the name of the game. I know a lot of guys who will also grip the stick (giggity) at the base, rather than toward the top where your hand normally rests, its a good way of dampening your inputs just based on the leverage of your hand position. I fly the hornet, so if you're doing the boom your visual que's and technique may differ slightly, but the core is still the same. Patience, and small adjustments, and never quit moving the throttle. If you keep it in one spot for too long, you're going to be behind the jet.
Hopefully something in there helps ya, you'll nail it dude, just keep on pushing!!
Also turn the wake turbulence off in the ME if its not already, it'll give you a little bit more grace until you get the hang of it, then once you're confident, turn in on.