If you haven't already taken him to the vet then I really suggest that you do before you give him away because:
The vet will be able to tell you for sure if he is a he and if he is neutered. Spaying & Neutering is very important and I would make sure that arrangements are made before you find kitty a home.
You need to see if he has any health concerns like ear mites, intestinal worms, FIP, FIV, or Feline Leukemia. This is very important. These things are very contagious to other cats and it's very to know if the cat has them in order to provide the cat a healthy life.
Good Luck and let us know what you find out. I'm not sure but if you are positive he is a male and isn't quite full grown, then chances are he isn't neutered. It's best he see a vet.