Anyone = any single person (it’s the singular form) Anybody = any possible people (it’s the plural form) Ex:does anyone have a pen that I can borrow? Anybody can learn to speak English. All people, but not a specific person.

I don't distinguish between the two. I consider them interchangeable.

They're exactly the same. Some people say 'someone' is slightly more formal than 'somebody' and others say the opposite, but that's largely personal opinion.