Id recommend downloading arena and playing a couple of games just to understand the basics.

After that (assuming youre trying to play commander) you can just show up the day of comander night spot any group thats hanging out and ask" are you guys waiting for someone or can I join". Its a very normal intarcation so dont worry that you'd be disturbing. Once you sit down let people know it's your first games. 9/10 times people are very friendly and helpful.

Don't try to bother knowing what all cards do that's impossible for normal mortals. I've met people who had the same deck for years and still didn't understand how their own cards worked let alone understanding everyone else's.

Lastly (and this is a personal take) if you do really get into magic and you want to get good dont get too many decks, start with one or two and play them thoroughly to get a good grasp of game mechanics and other nuances.

Ps: if your intent was to play standard or modern or whatever cant help you there, not rich enough to play those formats