I Am Looking Into Adoption

So, there is this girl I met for a while. I was her teacher in Asia. She has had a hard life and today she turned 17. I have always wanted to adopt her but wanted to wait till I enter the U.S. first. Now that I have my green card, I am very interested in adopting her. I just recently gave her money for her education. Anyone can give me some advice. I am now currently in Georgia if that means anything.