Buttons gave you very good advice, and you may be able to have him neutered before 5 months especially if he is at least 2 pounds. But the first thing to do is a trip to the vet.
The real problem here is that your breeder (if that’s what you want to call this person 🙄 ) did not socialize these kittens/cat at all. From the minute they are born, they need to be handled, cuddled and loved on which is what makes them so very loving and tame. It will just take patience and time for your kitten to learn about you, to trust you and realize that he has a wonderful loving home. No yelling, hitting, sudden movements that might frighten him. Just reinforce to him that you love him and are there for him. Get him some toys (wand toys are great and he won’t be going for your hands and feet and legs), kicker toys and a laser pointer that he can chase. Once he is tired out from playing, feed him in a quiet spot away from foot traffic, talk to him and see if he will let you pet him while eating. Then he will groom himself and probably sleep. He will find his way to you in the night for comfort and snuggling, but the breeder did him no favors by isolating him–as it’s almost as if he is a feral cat.