This reads like a shitpost. The math is eh, okay, but the explanations are totally wrong. I won't even try to figure out what "runs off watts" means.

Enough of any electricity source, using various converters can get any appliance working "technically speaking", but in the end the amount of energy available at the source and the rate of consumption at the end and any intermediates. So "technically" an AA battery can power an industrial electric press, but only for a fraction of a microsecond, using a lot of charge storing infrastructure and with a lot of changes to get the tiny bit of DC into the machine requires to operate, likely 3 phase AC power.

A proper explanation would say a lead-acid car battery provides power at around 12V and electric camping fridges nominally operate around 12V so you can connect them directly and operate it (so you can sorta say they both run off DC volts?). If not you would need a buck or boost converter. The available energy of the battery (Watt-hours is a useful unit here) and the consumption rate (in Watts) of the fridge determine how long you can use it on the battery.

Accept the battery is DC 🔋and fridge runs on AC🔌

Sounds like a jippitty conversation.

classic example of being wrong with authority.

I thought America runs on Dunkin... (doughnuts)

No easy conversation from doughnuts to volts or amps. I give up. But with enough oxygen you can hear up pretty gud with a single doughnut. Then you could use a Stirling engine to pump heat from the fridge to the environment. Energy in a doughnut ~224cal according to Wolfram alpha. That's 940kJ. 940kJ/1hr~260watts which should run a fridge for 1 hr. However energy conversion is probably going to leave you with like 10% at most of usable energy so ~6 minutes run time. America needs a lot of doughnuts!