What kind of cooler should I get for keeping hot food?

Get a rotomolded cooler (like Yeti, RTIC, Pelican, or Orca) because cheap injection-molded ones can warp or crack from heat. Rotomolded plastic is denser and thicker, with better insulation, so it holds heat longer without damage. Preheat the cooler with hot water for ten minutes before adding hot food, and never put hot food in a cooler that was just full of ice.