Gods is the plural of god, the masculine form of a diety, and is often used to refer to both sexes, with Goddess being the feminine form, just as actors as the plural of actor is used to refer to actors and actresses collectively. So, yes, Gods can be Gods and Goddesses, unless your intent is to be gender specific, then Gods can only be male.
I never quite got why God in Christianity was made masculine. Wouldn't it make more sense that the creator and giver or life be female... considering thats the norm throughout nature and the beings "He" created... Christianity hates women.
We all have our own ideas of what a god is, and to ask that, is to imply that everyone believes in the same doctrine, which is completely absurd. There are many different cultures around the world, and each of them has their own type of deity, so to say that one is the true god, is to say that all the other cultures are wrong in believing what they believe. I say, believe what you believe, and leave it at that.
" No one really know." - You do not know what every single human being in the world knows or does not know. How do I know this? That's the entire point. I don't, which proves that neither do you.