Re: Given Names and Surnames
Laws on this may vary from state to state.
My cousin was not able to be present at the birth of his daughter to a woman he was not married to. She was not allowed to list him on the birth certificate and name the baby his last name without some sort of paperwork - an affidavit of paternity or some such thing. I can't remember the details now, but I was surprised. I learned that a woman can't just have a baby and say "Joe Blow is the father and the baby's name is Josephine Blow" without Joe being part of that.
I did know one couple who named their daughter with the wife's last name (she did not take her husband's name at marriage) and their son with the father's last name.
No, there is no requirement - legal, religious, or social - to change your name when you marry.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.