The main problem is that I can't watch videos on youtube more than a few seconds without freezing and I don't know if its a Network update I need.
The video streaming from internet platforms like youtube needs to be buffered (cached) before the steam would start.
So possibly your internet connection is slow or the server are overloaded.
By the way: what internet connection do you use: WLan or LAN?
Please check if the slow data transfer happens with both connections.