One who is about to become Catholic by being received into the Church (already baptized) can and should go to Confession just before that happens. See the earlier post.
If a Protestant has many of the same beliefs as the Roman Catholic Church, does the individual still have to go through RCIA?
Yes, but not necessarily what you might be asking.
All adults who are coming into the Church come in through the process of RCIA. There are different forms of RCIA. There is one for the unbaptized; this form would not apply.
There is also a form of RCIA for the previously-baptized.
Exactly how one goes through that process can vary by individual. Most parishes (at least larger ones) have group classes for these candidates.
The process does not have to be a lengthy one.
In my own parishes, I’ve occasionally had situations where someone was non-Catholic but had been attending Catholic Mass for decades (married to a Catholic), and participating in parish life in every way except for receiving Communion. For them, all that was necessary was a brief ceremony receiving them into the Church, then Confession, then Confirmation and Communion at the next Mass. Because of their situation, they did not need formal classes. Even though it’s much shorter than the typical RCIA format (ending at the Easter Vigil) it was still RCIA.
I am someone who holds the same beliefs of the Roman Catholic Church even though I am a Lutheran. I am 16 but when I graduate, I am planning on leaving the Lutheran Church over many issues.
I believe that Confession is a Sacrament but I am still questioning Holy Orders, Holy Matirimony, Anointing of the sick, and Confirmation. In the Lutheran Church we only consider Baptism and Holy Communion as sacraments.
Because you’re a minor, I must tell you very clearly that nothing you read here should be taken as suggesting that you do anything against your parent’s or without their knowledge.
When you’re ready, talk to the nearest Catholic priest and he can guide you on the right path to becoming Catholic. Everyone’s situation is different, but no matter what, he will be able to guide you through the right program at the local parish so that you can become Catholic.