Why does the Catholic Church hold the deuterocanon is infallible?

Hey, from a Lutheran Protestant, I only read from a Bible that has both the Protestant canon with the “apocrypha.” I think the books are useful to read and have good wisdom, but it doesn’t make sense to me that we should hold them to a higher standard than the canon used by Protestants. The Apocrypha was only used by later Jewish communities, and the Old Testament already affirms what the New Testament reveals. I’d like to hear your thoughts. God bless!

(PS, favorite verses from the deutercanon? Mine’s Sirach 6:14)