Why NETFLIX eats so much internet, and why. What can you do about it?

Hall, ask is my brother is always watching Netflix at 9 pm on his XBOX and then I have a 1000 ping what can I do about it? I tried to ask my brother if he could stream in SD (but because my brother and I do not get along so well with each other) so he does not want to do that and I wonder what can I do there?

Please answer as soon as possible that is going to me nähmlich slowly on the nuts

PS: I'm not the best at writing German I'm going to school in France

If you have access to your router, you can screw it down the bandwidth.

In the Fritzbox for example via Internet → Filter → Prioritization.