hello! Listen, please don’t worry about how your questions sound. They’re not stupid, i promise.
We don’t have a confession per say, but we do have something called “tawba” which in arabic means “retreat.” It’s a type of repentance in which you basically just absolve to stop doing whatever sin it was that you were doing and return to what God commanded. You don’t have to talk to anyone about it, it can be just between you and God. You can if you want to, though- if telling someone might help you feel better, you can talk to a sheikh or anyone you trust. You can do it as often as you want and whenever you feel ready to.
In any case, all sins are forgivable if the person sincerely repents.
“O ‘Ibaadi who have transgressed against themselves (by committing evil deeds and sins)! Despair not of the Mercy of Allaah, verily, Allaah forgives all sins. Truly, He is Oft-Forgiving, Most Merciful” [al-Zumar 39:53].