Apple watch S6
Does Apple Watch Cellular supported in Saudi Arabia ? and if I buy it from outside Saudi it will work ?
Saudi Arabia is not listed on this page of carriers that support the Apple Watch
https://www.apple.com/watch/cellular/
You can get a GPS only model which will do everything the cellular model will do as long as your iPhone is nearby. If you get a cellular model it will behave as if it was a GPS only model.
As to Apple Watch cellular radios, there regions with radios dedicated to each
- Canada, U.S., Mexico and Puerto Rico
- The rest of the world