How do I adopt my new wife's daughter?

Hi I am looking for information on how my husband can adopt my daughter. Her birth father left early on in my pregnancy and i have not had any contact with him since. His name is not on the birth certificate, in fact the space was left blank because he wasn't there to sign the papers. It has been one year since my daughter was born and my husband wishes to adopt her. Can he just sign his name on the birth certificate as the father or do we have to do some other legal paperwork?Any help would be appreciatedthank you ccrc16