WiFi uses less power than a cellular connection, but detecting WiFi nearby uses a lot of battery.
How to only enable Wifi when you are at home (or at work), and turn off when you leave in the Shortcuts app:
Only turn on WiFi when you know you have a connection
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Limit when and how often apps access your location
Apps accessing your location is a major source of battery drain.
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13 iPhone Battery Saving Tips to Extend Battery Life
How to improve iPhone battery life with low power mode, background app refresh, location services, and more settings