You actually become officially Catholic at the Easter Vigil during the renewal of baptismal vows and the profession of Faith. If you are baptized validly, then it is your declaration of the Catholic Faith that makes you Catholic. My 3 kids are Catholic and they have not been Confirmed. Confirmation doesn’t make you Catholic.
So, because it depends on your declaration, you are in a interesting situation as soon as you come to believe and Confess the Catholic Faith. For the sake of ceremony, preparation, and order, we postpone your official entrance until the Easter Vigil.
But, technically, anyone in RCIA who dies while in RCIA is considered to have died a Catholic. So, on a technicality you are already Catholic. But, you are postponing your official public commitment to the Church until the Vigil. RCIA has a long tradition and is the current norm, but there is nothing super set in stone about it. The Church could speed up the process for baptized converts if they wanted to, and I’m sure in some cases it has been done.
RCIA is also perhaps in its origin, more for those who are not baptized. Remember, it was over one thousand years before there were baptized Christians who weren’t Catholic that needed to become Catholic. Before that, if you weren’t catholic, you weren’t yet baptized, because there was no other Christian group to be. So, RCIA began as a process for the non-baptized. The non baptized don’t go to Confession before the Easter Vigil because Baptism forgives all sins.
So, to answer your question you are most likely already technically Catholic, but your’e waiting to making your public committeemen at the Vigil at which point you’ll also be receiving the sacrament of Confirmation and your first communion.
Congrats and welcome…fortunately it is getting close and the weird in between time warp state you are in is about to close!
