Betta Fish: Update: my sister’s betta fish

I don't know how to post an update but basically my sister has a betta fish, it's not in a good habitat and they don't check the water or change often it or anything, so I am trying my best to make another tank that's better for him. This is what it looks like so far, I put hornwart and… something else… (I can't remember) And I was wondering what else I need, but be aware, I have very limited money for this. (I got the test strips instead of the other one because it's too expensive, and I just want to know if that's genuinely wayy crazy and I should be condemned to hell or something)