"many Agnostics are Atheist".   Drivel.

Words mean something. I refer you to Mr. Dictionary.

I've given the definitions for the two from my dictionary, earlier in the thread.

If you ask an agnostic if he or she is an atheist, how many do you think will say yes?   Pick a small number.

Most are very likely sensible people, like Einstein, who in general wanted it clear he was agnostic, not atheist.

As I said, agnostics can live with a large degree of uncertainty on many philisophical questions.   Atheism assumes more certainty than is justified.