You can have your iPhone turn off Wi-Fi by itself, or change just about any setting, whenever you leave home or come back. Here’s how to do it.
Apple has included a way for your iPhone to register that you’ve left home, or any specific place. It’s through a Shortcut automation action, which means once you’ve set it up, you can have your iPhone do anything that Shortcuts allows — just by leaving somewhere or returning.

I always knew that leaving WiFi enabled when you were away from a trusted network was draining your battery, but I never considered the use case of iOS Shortcuts as a way to automatically disable it when moving from place to place. I trust two WiFi hotspots only – home and work. Everywhere else, I won’t connect, so no need to have it active.