Hi

It's not, but it's not impossible. I personally trained first in the sim using a PS4 controller, and you can somewhat learn well using thumbstick extenders, but there's a certain handicap with throttle control due to the stick always snapping back to the center.

what controller do u recommend?

I'm still using a PS5 controller, but many use the RadioMaster Boxer or RadioMaster Pocket controller right now.