I think that what King Les was trying to say, is that loving a bird is pretty complicated. When you first meet your new family member, everything is so cute and loveable that it's really easy to give your whole heart over to him. Believe me, I know how it is. I wasn't much older than you are when Mr Mollie came into my life and I would thrown a fit if anyone had told me how ignorant I was when I got him.
BUT - if you ignore all of the things about Tristan's history (like where his parents came from or how adults behave differently than babies), you are ignoring a pretty big part of who he is. And if you choose to ignore those things now, when he's cute and cuddly, it's going to be really hard to keep loving him when he starts some of the really bad habits that often happen to hand-fed cockatoos. If you know about these things before they start happening, you can make changes in the way that you deal with him that can help make his life with you a better one.

Take some time to digest what we've shared with you. I think that you should bring your dad to this message board. The people here are treating you like an adult, so you need to decide whether you are going behave like a child and throw a snit every time that someone challenges you, or whether you are going to read and listen and learn. Twelve years old is old enough to make that kind of choice. Tristan will be better off if you stay.