Betta, mystery, Serpae tetras, von rio tetras, golden shrimp... also some bladder snails that snuck in on plants.
I honestly LOVE my mystery snail, “Turbo” - very entertaining. Watching him ride the bubbles from the air stone up like an elevator and then glide down onto a leaf... dude is cool.
Also I don’t hate on snails like some do - they are an indicator of tank health and if you have an outbreak, it could just be due to too much food present for them to eat.
Once tank balances so will their population.
They do a great job of keeping tank clean.
I also put live black worms in regularly and have them living in the gravel. Once you get set up, I highly encourage live food, it brings out the color and true nature of the fish.
Definitely get shrimp though if no snails, those dudes are cool to watch and lightning fast!