The Catholic Church does not recognize the LDS ordinance of baptism as valid. Unless the OP was baptized in a recognized Protestant denomination, they will be baptized as part of their reception into the Church.
I’m Mormon but I’m interesting in joining Catholic. The problem is that I have committed adultery a long time ago and before I join Catholic during Good Friday weekend, I’ll need to confess the priest, would I be forgiven and become Catholic.
If you’ve been Mormon your whole life (you have only been baptized as a Mormon), then you will have to be baptized and thus not need to confess your prior sins.
But for future reference, any sin can be forgiven.
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