New to Rivals, would appreciate any advice/tips

I have just downloaded rivals and have no idea what to do, I've played Overwatch 1 & 2 for years so im super familiar with the menus/characters/attacks etc from Overwatch but i don't really know anything about this game, also what are the different classes? I'm obviously used to tank, dps & support (I main support in OW) but the rivals classes seem to be a bit different so I'd like some help in understanding the classes and who/how I should focus on playing and any other beginner tips you can offer would be greatly appreciated. I did get in for a bit and mess with some of the characters and abilities in the practice range but I thought it'd be a good idea to get some advice from the subreddit before heading into a game and just being annoying for everyone on the team cos im fresh to the game.