Front AC wiring to plug into 20 amp

[scuba dude]

Has any one wired their front ac where they can run an extension cord from camp ground pedestal 20 amp. This is something you would do if you are camped at a location with only 30 amp hook up and you need to run both acs in summer. This is a common thing where you are camping at coe parks. I have done this before but I now have a new 2020 3813 and its a different set up completely. Having problems figuring out wiring from breaker to ac