For the vast majority of the situations in a English-speaking society, the term for that type of person is a "white supremacist". For example, a person who does Nazi salutes, or wants to update refugee policy so that the majority of immigrants are White South Africans, is a white supremacist.

No, that just describes white supremacists, and ignores Black supremacists, East Asian supremacists, Hispanista supremacists etc.