Can i change my sons name if i was never married to my kids father but his name is on the birth certificate

After you are married, you can petition the Circuit Court where you live for a change of your child’s name. You will need to serve the out-of-state birth father with a copy of the Petition but it sounds as if the father will not respond to the suit. If he does not answer, you can prevail by default. Note that a name change for a minor (like an adult) needs the completion of a background check of you by the FBI and the Florida Department of Law Enforcement. You must have a set of two fingerprint cards to send each agency. You can expect a delay of a few months to receive the criminal background checks.  If successful, you can request a new birth certificate to be issued out with the new name.  This sounds very bureaucratic and it is. I would recommend you have an attorney assist you.