Apple Watch without phone support
After you set up an Apple Watch 7 with cellular service, do you need a iPhone to support it?
Yes. You will ALWAYS need a companion iPhone to do things such as update WatchOS on the watch and manage certain features on the watch. Apple Watch is NOT a standalone device. In addition, cellular service is tied to the phone number on the iPhone the watch is tied with and it won't work unless its time to an iPhone.