Hi, please help me.

"Everybody has the right to state their opinions."

Is it possible to replace "everybody" with "anybody"?
If possible, the two sentences have different meanings?
Both are valid, with no change in meaning, as far as I can tell.
It sounds better with "everybody," and it seems to be all inclusive in meaning. At any rate, for formal standard English, both are singular, so "their" is not correct in the sentence, though many people would use it in conversation.