My mother was Protestant, and my father was Catholic; so the two of them decided between them (since it was a bigger problem for my father's religion than for my mother's if someone raised their children in another faith) that my siblings and I would be raised Catholic.
So, I was born into it, I guess; and I grew out of it, as well as growing out of a lot of the other things of my childhood.
The Catholic Church was never really able to convince me of much of anything, though; because, to a six-year-old who knows how good and kind her Protestant relatives are (and who knows "there's also such a thing as Jewish people", a guy who stands there in satin robes and a hat and who says, "Anyone who isn't Catholic is going to Hell," doesn't come across as if he knows what he's talking about when it comes the God that's supposed to be the same God for all people.
For anyone who may be wondering if I then adopted my mother's religion - nope. As far as I was concerned, while I had my axes to grind with the Catholic Church, at least it mostly emphasized "God", with only some reference to Jesus. Protestant religions struck me as forgetting "God" and focusing only on Jesus - who discussion for another day (and one I won't be having here or any time - ever LOL ).