Apple iPhone SE
iOS 15.0
1. Find "Wi-Fi Calling"
Press Settings.
Press Phone.
Press Wi-Fi Calling.
2. Turn Wi-Fi calling on or off
Press the indicator next to "Wi-Fi Calling on This iPhone" to turn the function on or off.
If you turn on the function, press Enable.
3. Return to the home screen
Press the Home key to return to the home screen.