Last week I received a rescued Golden Retriever. His name is Boy. Is it too late to change his name in some way?

Last week I received a rescued Golden Retriever - age 6-7? Still has a lot of puppy in him. He needs proper training but is a wonderful dog. His name is "Boy." is it too late to change his name in some way? All I know is that he originally came from a pound in GA and the family moved to PA but were told to give him up. Boy is the only name he knows so I understand keeping that but, I think, he deserves something a bit more like him. And yes, he is a boy. Eager to hear your suggestions on this issue.

Barbara