Name Change Laws in the U.S. - BabyNames.com
Changing your first name. As with your surname, there is nothing in the law stopping you from changing your first name at any time, so long as you don't have any fraudulent (or other criminal) intent. You can assume any name or combination of names you please in addition to, or substitution for, your existing name.
https://babynames.com/names/name-change-laws.php
https://babynames.com/names/name-change-laws.php