I want to adopt my nephew whom I've had since he was 6mos old and whom I also have custody of. I want to know if I can file the paperwork myself instead of paying thousands of dollars to a lawyer and if so how do I get started on this journey to adopt my heart and soul?

Where did you get the idea it would cost thousands of dollars? Generally its usually less than $1000. The only kicker would be getting the bio parents to relinquish their rights.

Speak to someone from legal aid. They maybe able to give you sound thoughtful advice. And then you will have an idea of where to start. Especially approaching both parents for relinquishment/adoption proceeding's.