I don’t think it’s a case of “convincing” them. Tell them that you’re curious about Catholicism and you want to explore the faith. If they are confident in their Protestantism, then they have no reason to fear Catholicism. If not - well, what are their doubts about their own faith?
In terms of resources, Scott Hahn has some excellent books that you, and your parents might find helpful. I’d suggest you start there.