2000 watt inverter generator how long could i run it off 20lb propane tank honda 2200 last up to 3.2 hours 1-4 load and 8.1 under full load?

How long would 20lb propane tank run the generator or longer

The generator specification sheet should tell you the fuel consumption rate.

As 'oil field trash' stated, the specifications should have the information needed to find an answer.
The numbers you give Can't be correct because you claim 2.5 times as long under full load as under whatever you mean by 1-4 load. BY DEFINITION, it can NEVER operate under more than full load.

8 hours at full load. Your refrigerator/freezer alone is probably 1/3rd load -- more at startup [so startup the 'fridge with nothing else plugged in at all].

ps: you only need to run the 'fridge about 8 hours a day o keep freezer solid. Candles are cheap way to light your evenings, use them instead of the generator

No problem.