A brother who scares me?

I was riding in the backseat of his car with my dog, and my 20 year old brother was playing on his phone and drinking a shake while driving. I asked him to stop and he said this is my car I can do what I want. I said it’s respectful when someone feels unsafe in your car. He said you have to give me a reason I can do what I want why would I want to respect you I shouldn’t have to respect you. And then he started dragging it on and on saying nasty things.