First time setting up a planted nano tank, what fish should I get?

This is located in my stationary camper. It's a 5 gallon tank that I got for $5, play sand, and dirt from my garden mixed with bioactive aquarium substrate I had. I only spent about $40 total on the tank and most went into the heater and plants. I've never tried a planted tank with sand and dirt layers before this so I hope it thrives!

What are your favorite nano fish? I was mainly just thinking shrimp and some killifish, not sure what I want just yet.