What are the qualifications for an fha loan?

If you credit score is really bad but you repair it to an extent, I mean if I can get it to around 620 can you qualify for an fha loan in GA? I also have 2 old bank accounts that were closed due to overdraft fees that I never paid (also debt) should I pay these? It’s not on my credit score as a debt or collection but I’m not able to open any new bank accounts because of it… I have filed bankruptcy once as well, over 4 years ago. Is there any chance I can ever qualify for an fha loan