Can a human being become God and live forever? Have this incident happened before in the history? (a normal being becoming God and stays as God till now)
No, that is NOT possible. Gita says:
2.27 For death of anyone born is certain, and of the dead (re-) birth is a certainly. Therefore you ought not to grieve over an inevitable fact.
So no human being who was born can become immortal. Exception proves the rule. In the list of chirajivis, a few are human beings.
And no one can become Ishvara ( God) as God is only ONE. It is not correct to translate God as the Formless All-pervading Brahman, as Adi Shankaracharya says that even the Brahmavid can NOT become Ishvara, Who is the controller of the Universe.
Again, from Gita:
18.61 O Arjuna, Isvara resides in the region of the heart of all creatures, revolving through Maya all the creatures (as though) mounted on a machine!
So Isvara is NOT some deathless human being living at a particular place. He is dwelling in each being.
So answers to all your questions is : NO.