30 amp plug if you have one AC unit, a 50 amp if there's two. You can't run the AC or heat pump on 20 amp but everything else should be OK. Campgrounds try to accommodate everyone, even campers who may not have any adapters but need to plug in for laptops, mattress inflators, etc.
You can get adapters (dog bones) to fit your house plug or convert a 50 amp to a 30 amp. Some of the 30 amp plugs are in bad shape at some locations so we use a 50 to 30 adapter and plug into the 50 amp.
Rich & Yvonne
2006 Safari SE -Dora-
2004 4Runner SE