Buy a starter deck. I recommend that because though it is crazy expensive IMO at some places ($20! But you probably have tons right?) but it's worth it, because it explains the rules to you and gives you, let's say, equipment.
Otherwise, check the current decks that are Tournament format and if you have some of them in those decks, work on making a 60-card deck. Try checking our TCG Deck Reviewing sub-forum, we have a guide to making your first deck!
Then, just play against a friend or something, and once you're confident that you can win most of the time, find out where a tournament may be held near you and start working your way up!
I don't know if you're willing to do that, but it's just a suggestion. Basically, create a deck and then do whatever you want after that.