How can you get banned on Twitch?

See above. When you insult you out of rage or something?

Amongst other things.

You could just look at the user guidelines

Insulting is not bad in itself, but certain words that you get out of your rage: Sch.tel, the N-word and meanwhile you are not even allowed to say Simp. (are only examples)

There are a number of other ways to be banned, e.g. Nudity, hate speech, etc.

Yeah well, … Certain people I always play with think it's funny to drop the bomb…

Then I would stream without these people, sooner or later you will be banned for it.