Maybe if you already bought the betta fish, one thing I used to recommend is to change up the decoration (add new plants, move the decór, etc.) within the tank. That way the betta fish needs to refigure out the territory along with the new fish.
This is how I did. I have two dwarf sucker catfish in the tank too, they don’t bother each other. And my Betta is only interested in interact with me lol. He likes following my hands around when I’m changing up the plants’ placement.
