My daughters bio-father had his rights terminated by the courts and is no longer legally associated with her in anyway how can I go about changing her last name to my last name? She wants her last name to be the same as mine and so do I

If his rights have been legally terminated, you would just have to file a legal name change with the courts.

That should have been taken care of twhen the rights were terminated. Now you have to petition the court for the change