Ok so I have this really annoying problem that whenever my brother uploads a video to youtube, I get like 600-800 ms pings on the games I play. I usually get like 60-80 ms when he isn't, it's 10 times as bad.

I've tried setting my priority higher than him in the network settings, that did nothing to help. I tried changing the priority of youtube, fixed nothing. He won't let me install netlimiter either -_-  

Easy solution:

Log onto your router usually by typing 192.168.1.1 into the URL bar

Fiddle around with the settings and turn his internet off. Some of the newer routers also allow to block certain websites, put internet restrictions and block certain activities (torrenting). Up to you!  

Upload will always bottleneck a connection. Most you can hopefully do is go into your router and maybe there is a setting to cap the upload.  

what router do you have?