The pronouns everyone, everybody, everything and the adverb everywhere are used in affirmative, interrogative and negative sentences, and are followed by a singular verb.
We normally use every when we are thinking of people or things together, in a group, to mean all, everyone etc. Every person in the theater clapped at the end of the play. (= all together).
Whereas we normally use each when we are thinking of people or things separately, one at a time. he made a speech where he thanked each person who helped him (= one at a time).