Betta Fish: My First Betta

This is Vash. I got him a couple weeks ago with absolutely no knowledge (aka impulse buy🤦‍♀️), but with extensive research and a lot of water changes + adding bacteria + lots of testing his tank is finally almost cycled! He seems to be doing really well, but I’d love some advice on how to keep him and his environment clean and healthy!
(P.S. I know his tank is pretty bare but I plan on getting more plants/other decor when I have the funds :))