Where are you located and where did you buy your phone?
Facetime has been restricted in some Middle East countries by the government. There is no way to get or use factime.
am in jordan
According to Wikipedia (OK, not always the most reliable source) FaceTime used to be disabled in Jordan but has since been enabled through a carrier update (which may also require an iOS update?) but new iPhones come with it enabled. Check with your carrier on how (if) you can get this update.