Two when running at space, one when going into contact. Depends really.
Ideally you hold it in two hands in front of your body when running with the ball. This gives you the option of an offload in either direction, which keeps the opposition from anticipating your move. Once you are committed to contact you (again, ideally) tuck it away in the arm away from your opponent so that you can use your near arm for a fend. This also allows the option of (once in contact) a pivot about the fending arm followed by an offload to a team mate who is giving vertical support.
2 when your running down the field so u can run pass and kick it u tuck it into 1 hand when your going into contact I have seen people run with the ball in one hand I don't know how well it works as im not able to palm the ball im too small
I often carry it in one hand when im going into tackles , wen in running down the pitch i carry it in two hands so im ready to pass or kick if im in danger.
It depends if you're intending to pass or not. 2 hands to pass, 1 hand to run. You can run a lot faster if the ball is in 1 hand but it signals to the opposition that you're unlikley to pass.
2 for the most part.
