Incorrect. Unless you were baptised Catholic, you are out of it.
"Roman Catholics, the largest U.S. church with a reported 69 million members, start counting baptized infants as members and often don’t remove people until they die. Most membership surveys don’t actually count who’s in the pews on Sunday. To be disenrolled, Catholics must write a bishop to ask that their baptisms be revoked..."Related threads:
....it is possible, for example, to be born Catholic, married Methodist, die Lutheran and still be listed as a member of the 1 billion-member Roman Catholic Church....
"...The Catholic understanding of membership is that a person becomes a member upon baptism and remains a member for life," Gautier said. "Whether you show up at church or not is not what determines whether you're a member."
-- from the thread When It Comes to Church Membership Numbers, the Devil's in the Details
"......The Dublin Archdiocese have confirmed that at the end of August changes were introduced to Canon Law and as a result it will no longer be possible for individuals to formally defect from the Catholic Church..."
LOL. Unbelievable. To paraphrase Hotel Rome -- "You can check-out any time you like, But you can never leave!"
For the purposes of the Inquisition it was sufficient to renounce the Catholic faih in order to be released to civil authority. You are correct, of course, that the baptism is an indelible mark that cannot be removed.