Anyone know the law/legislation JFK introduced which provided amnesty for people and their last names?

Under the Chinese Exclusion Act, I believe there couldn't be any new Chinese immigrants to the USA (beyond sons - I think?)

So many chinese people moved to American, under the pretense of being someone's son when in reality they were not. This was done changing last names and the like.

Any information on the law/legislation JFK made which allowed people to change their last names etc.