You must know this. For people body/one.
everybody/everyone means all. Somebody/one means one person of all but you don't know who.
Anybody/anyone in a negative sentence means zero people (I don't see anyone there) in a question means somebody/someone
(Can anybody help me?), in a positive sentence means one person or another(anyone could have kill him)
No one/body in a negative sentence is like any(i see nobody there) in the other ones means just no people.
The same for things and places.