Generally speaking, If it rolls, it's ailerons. If it veers without the roll, it's rudder. Remembering that this is a beginners forum, a lot of advanced instruction may be unnecessary at this point.

Some adjustment - trim is usually necessary, a couple of clicks one way or another is usually, probably necessary on the first flight of the day. Once done at flying throttle setting - meaning take off, level out at some throttle level, not full open, although some people think the throttle is a switch.. full open or fully closed , set the throttle for flying, perhaps a couple of clicks over half, then trim the plane for straight and level flight and fly on.

Some times, this is done on the maiden and can be adjusted out mechanically after the flight. Sometimes, this takes several flights to get it right, but once done, you can take off, set the flight throttle setting for what I said was flying speed, then make the minor trim adjustments for straight and level, and then enjoy it and fly the plane.

CGr.