Can myboss cut me from 40 hrs to 32hrs without a legitimate reason

Unless you have a contract or union, yes.

Can my boss cut my salary from 40hrs to 32hrs without any reason at all or for any reason

We're all volunteers here - please give us more than 4 minutes to answer.

The answer is yes unless you are specifically protected by contract or a union.

Can my salary be cut from 40hrs to 32hrs for reasons that I stated the boss made sexual advances to me

You might want to take that up with your HR department if you have one.