https://www.consumerreports.org/home-garden/generators/buying-guide/
It actually covers the basics, even for Consumer Reports.
More here:
https://norwall.com/power-expert/How-to-Use-a-Portable-Generator-for-Emergency-Power/
I don't know about whatever you bought, so this is general. Don't know how long a 20 pound tank will run.
Before anything else: If you are talking two-phase 120-220, you are talking backup generator, not an emergency generator.
Such generators are permanently installed and have a transfer switch as part of the installation. Over 5 kw, IIRC.
I have a backup generator.
Emergency generators will keep your food cold and the lights and gadgets on. But be damn careful. See below.
First order of business:
Never backfeed into your home power without a transfer switch. Period.
Know your electricity or ask a real electrician.
Period.
Second order of business:
Keep it away from the house. Exhaust, even from propane, is a no-no.
3-5 days is about right for a gas generator. I hate gasoline, yes and I have a big Generac that will power (and has ppwered) the home for weeks. ( fire danger in the area) It runs on propane.
You can check, but if you have natural gas piped in, it usually works during power outages. They may shut it off during fires.
Make sure that the generator is jetted properly (if natural gas or propane).
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