Just a quick question which I'm sure I'm over complicating in my head.

I've read that Helium 4 is a Boson because it has 0 spin and that Helium 3 is a Fermion because it has 1/2 spin. Is this right? I don't see how whole atoms can be associated with fundamental particle groups.

Why do each have those particular spins and why does that constitute them to be either Fermion or a Boson.

Also one other thing: Is it "integer spin" or "integral spin"? Do they mean the same thing because I keep seeing them being interchanged when talking about Fermions and Bosons?

Many thanks in advance for your help.