You buy a backup generator.
Everyone here in NH has one.
I have a Honda 7500 watt.
I can run everything in my house except my electric oven, stove and dryer which all have 30amp breakers.
If you have propane or lucky enough to have natural gas (NG is rare here) you get a backup generator that runs off of gas.
My daughter has this system.
With their underground tank, they can run their house for 3 weeks with a full tank.
The downfall of a gasoline standby generator is that they only have a tank that will run for about a day.
So, every day you will need to run to the fuel station to refill your gas cans
I know the value of a generator. it isn’t electric.
I ran a generator on/off for a week with no power in NC. Until the propane tanks were getting low. Takes power too to refill propane-which no station had to pump it. But storing propane beats storing gasoline any day of the week