Has Everybody or Have Everybody?

The correct form is “everyone has.” There are very few cases where “everyone” would ever be followed by “have,” but, for the most part, you will always use the singular “has.” And, this may strike you as odd at first, but you'll understand why in a minute.

Is everybody singular or plural?

These words—“everybody” and “nobody”—are indefinite pronouns, meaning they don't refer to a particular person. Both these indefinite pronouns are singular.

Has anyone or have anyone Which is correct?

Although “anybody” is in the third person singular, and hence the correct verb form used with it must contain an “s” (as in “anybody who has read the book …”), “have” in the situation described above is the only “correct” option.