My friends and I do this a lot on board game arena - it's nice because you can only make legal moves there (and trying to make an illegal move usually faces you with some context as to why it is illegal), so it's easy to explore part of the game's state space without having to know anything about the rules. Then after some number of rounds we'll read the rules and figure out how things worked that we missed, and then play a real game. It's quite fun.