No they believed in their 12 gods and goddesses
Greek gods are as real as any other gods.
If you are talking about God in the Bible, yes. If you are talking about gods in particular like Greek gods, no.
No
from the Greek word "bibile" meaning gods rule book. it speaks relatively to, about, and is from gods view.
It doesn't cause djinn is part of the greek gods mythology
Just like any culture or religon they have gods.
There aren't any powers the Greek gods could not have called upon in myth.
There were 12 main gods, such as Zeus, Poseidon, Aphrodite and Hermes but there were loads of minor gods, unfortunately i don't know the names of any greek minor gods :( Hope this helps you :D
No.
There isn't any particular terms for older Greek gods -- unless you mean the Titans, who weren't gods, but Chronos sired six of the original gods and goddesses.
No there are not. Greek Gods are treated as mythology these days and not seen as something to worship to.