There are billions of Greek gods and goddesses, but the 12 main ones, or Olympians, are Zeus, Poseidon, Hades, Apollo, Artemis, Hera, Aphrodite, Hermes, Dionysus, Hephestus, Demeter, and Ares. Sorry I don't know what their order of power is.
The ancient Greek Gods did not have second (or family) names.
They were the religion of the ancient Greeks.
No, they worshiped their own gods/goddesses.
No; the female goddesses in ancient Greek religion were not inferior to the male gods.
it gave them something to believe in
They were real gods and goddesses to the ancient Greek people, yes.
Greek myth does not list birthdays for ancient Greek gods and goddesses.
Yes. Many people believe in Greek Gods/Goddesses. I believe in them.
Yes
Greek gods, and goddesses drank wine.
It's impossible for a mortal to become a God
According to ancient Greek mythology, the universe created the Titans and the Titans were the parents of the lower gods and goddesses. Therefore, the gods and goddesses were the grandchildren of the universe.