1.vvardenfell was destroyed and Morrowind attacked by argonians ,and the house telvanni ended?
Vvardenfell was rendered uninhabitable, but it's still there. It's been repopulated already because characters in Skyrim talk about people living there.
House Telvanni wasn't destroyed. Its ruling family was killed, but it's still a thing. There's a woman studying at the College of Winterhold from Telvanni.
2.Morrowind doesnt belonger to the empire anymore ?
okay these are my doubts, i hope you can anwser me well because if the empire didnt left Morrowind why arent they helping i know that they have thalmor but still:
Morrowind is still a part of the Empire, but the Empire is far too spent to do much about their situation right now.
3.Elsweyr is divided by 2 empires dont understand that is one that is from the empire and other rebels?
It's two kingdoms, not two empires. It's actually the way Elswyr always used to be before the Third Era. It's nothing new. They're not even against one another. Maybe their people just feel like Khajiit society works better that way.
the 2 moons vanishing, and 2 years later appear and the Khajiits thanks thalmor for that? why? (im not sure because i′ve seen all these in UESPwiki i know it isnt a good place but all my doubts were solved there, well until now!)
The Thalmor took credit for the moons coming back, saying they used ancient magics to do it. For all we know they made them disappear in the first place.
and what are the provinces that dont belong more to the Empire?
i think it is : Hammerfell, Elsweyr and Black Marsh but im not sure
The provinces that are not in the Empire are Summerset Isles/Alinor, Valenwood, Hammerfell, Black Marsh and Elsweyr
Orsinium might or might not be. Not sure. Probably isn't in it any more, since they had a pact with the old Orsinium which was destroyed.