AI Dungeon exists, but you'll have way more fun if you find a group to play with. If there is a game store near you then they can definitely point you towards the right places (and probably host beginner-friendly events anyway). There's also Adventurer's League, which is the publisher's way to try to welcome people in to the hobby. It sacrifices some ofthe freeform nature of the game but in return you get some contacts and a pre-arranged code of conduct for everyone