If you are going through RCIA process you will be asked to choose a saint name as your confirmation name. I believe high schooll aged kids do the same when they are baptized.
I’m not sure if it’s required but I’ve never heard of anyone refuse to do it.
My confirmation name was Joseph. I chose that name because my grandfather’s name is Joseph and the husband of Mary is St. Jopseph. There was a connection there for me bacuase Joseph assumed the fatherly role with Jesus even though he knew Jesus was not his son. The man I called grandfather, is not in fact my biological grandfather. I was born to a single teenaged mother and had no father. My biological grandfather was abusive to my mother, grandmother and uncles and my grandmotheer (Not Catholic) got a divorce from him before I was born. My grandmother remarried to a guy named Joseph, who took my Mother and uncles in as his own children. My mother and her brothers always refer to Joseph as their father, not their biological father. He also took me in as his own and we had a very special relationship from an early age.
So, I chose Joseph because he accepted Jesus and my Grandfather named Joseph accepted my mother and uncles, along with me, as his own even though he had no obligation to do so.
I really think it’s a great thing spiritually. It can be a way to model your faith after a saint and always have a reference to the roots of your faith. Sometimes over time you can forget things about how your faith was formed and things that were important in that process. Having a saint name that has solid meaning to it can be a reminder not to forget what excited you in the beginning.