I would like to know if my iPhone is official unlock or not

I don't know what that means. If you are referring to an official unlock from a cell service provider borrow a SIM from someone not on the same provider and see if it works or call AppleCare, tell them you just want to know if your iPhone is locked to a cell provider and give them the model and serial number.

Depends on where you bought it.

In the US, only phone sold at Apple stores are unlocked. No other store sells unlocked phones.

~Lyssa