Most native food is composed primarily of buffalo meat, fish, corn, tomatoes, potatoes, and berries. Basically just whatever they happened to be able to find and/or farm. Buffalo chili is phenomenal, (buffalo is red meat that is much leaner than beef, so it tastes a lot like beef chili without all of the grease) but maybe not something that you’d want to try as your first undertaking.
Fry bread is quick and easy, but a little bit messy if you’re not accustomed to frying things. Fry bread was often used by many tribes as a sort of base for many of their dishes, sort of like tortillas in Mexican cuisine. It’s dense and fluffy at the same time, because the dough bubbles unevenly as it fries.
And speaking of Mexican cuisine, there is a lot of overlap between native dishes and traditional Mexican dishes, because many native tribes (especially the ones in the southern US) were proto-Aztecan cultures. Remember how I mentioned tomatoes? Mexican salsa has roots in native cuisine. Hell, my own tribe’s language has the same roots as Aztec, the same way english and German are both derived from the same root language.
You might give fry bread a try. There are a lot of recipes available, and it can be topped with either sweet or savory ingedients. I suggest a recipie that uses shortening for frying, but thats what my grandma used to use so I am biased. Cheers!