I’d say the way to learn is just put a small amount similar to if you were to put sats on a custodial lightning wallet. You don’t need to tie your identity to it. Don’t put all your margin into a single trade probably limit your leverage in the beginning. I’ve used it for over a year and have had no issues with withdrawals. Anyway it’s a risk but it’s a good way to learn. Check their webpage for info. Don’t know all the specifics about where the margin comes from etc. or don’t it’s not for everybody.