Why do Buddhism teach people to be no one?

It is also hard for Buddhist because the paradox of I am Buddhist.
I don't mean in name, many people are so but They desire to be someone.
Westerners' theory are so Christians... are ego.
however do you feel you are someone then you can't do other?
Buddhism's no one is infinity because that is start point newborns actually in reality
the you can do everything without be tied with ego.
but how do you stop you to be someone? if you move
that is westerners confused on theory. You get it as Dr. Feynman's words?
Why do Buddhism teach people to be no one?
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