Human Beings follow (belong to) many different religions as their "way of life".

Even an atheist, agnostic, scientologist or whatever can follow his beliefs 'religiously'. A religion doesn't have to be to do with belief in any God.

God doesn't 'belong' to any religion. We mere humans usually do.

God is believed by some/many/most(?) to be the Creator of the World (as we know it); the Maker of Mankind; a supernatural being; omnipresent and eternal.

The last paragraph, of course, depends on who's particular God(s) you are referring to at the time!