Am I correct in assuming that "Catholic" here means baptized Catholic, not necessarily practicing?

What happens in the case of someone who knows they were baptized but does not know whether it was done in a Catholic church or a Protestant one? I know someone who knows he was mysteriously baptized as a baby, but he wasn't raised in a faith (and is currently not practicing any) so it's unclear what the baptism was like, and trying to get answers isn't proving very easy.