I'm trying to place my apps on my XS Max, but since I only have Xcode 9 I can't get it to work on the arm64e architecture. I've tried to update the MacBook in order to get Xcode 10, but since this is a school MacBook, they restrict updating to High Sierra.
Any help would be appreciated. Thank you.
You cannot use an iPhone XS Max with Xcode 9 (nor a simulator, neither a physical device), since it runs iOS 12+, for which the debugging support is only available for Xcode 10 (and newer).