The general rule in Florida is that a child's surname should remain unchanged absent evidence that the change is necessary for the welfare of the child. Thus, absent the father's consent for a name change, you will have an uphill battle trying to convince a court to change the child's name. As parents routinely deal with doctors and schools despite having different surnames than their children, that's a very weak argument to use to try to convince a court to override the father's objections.

If the background is a paternity action or an AOP, then we're talking about a case in which you chose this name for the child when you applied for a birth certificate, you and the father mutually agreed to the surname when applying for the birth certificate, or the paternity court granted the child the father's surname as part of the paternity litigation that established the father's parentage. This is thus not a situation where a court, entertaining a dispute over the surname, is trying to resolve that dispute -- it's a situation in which there was either prior agreement, or a prior court ruling on this very issue. It's much easier to convince a court to give a child a hyphenated surname if there is no prior agreement; but where you either agreed to the name or had a court already rule on the issue, it's a much more difficult case to make.