I was baptized at 31 days but confirmed at 21 years.

A good religious education program would likely have given you more knowledge than you currently have but you are entirely free to start your own education now. I did not know anything at all about Catholicism until I was about 15 years old (except for what Jack Chick and a few others of his ilk had told me). Seven years of study both formal and informal and I am still learning more and more.