How do I go about changing the name on my son's birth certificate and putting mine ,the name that's on there now is'n the father

Law varies from state to state.
It depends on several factors.More information is needed.

The amount of time since birth and if the US the state, makes a big difference.

Next is the man listed the husband,

But you will hire an attorney and file for paternity test to prove you are the father and ask to be reconised as the father.