Is there a reason why you don't use Airplane mode at home with WiFi switched on?
If you want to use mobile calls and SMS at home, this is also possible in Airplane mode if you have activated Settings> Network & Internet> Calls & SMS> your provider> Use Wi-Fi calling
.
If you then leave your home, Settings> Network & internet> Internet> Network preferences> Turn off WiFi automatically
ensures that it is automatically turned off x minutes ( you can set and configure a timer) after it is disconnected from WiFi.