What can help this baby?

there's a child in my life and he was born premature he looks like he is 5 or 6 mos old but he is 15 months old and he can't control his coordination( he can't control his head and neck) is there any exercises i can do for him to help him get better? he has an incision in the upper middle part of his back and it my not be completely well. serious suggestions are welcomed