when I turn my xbox one, it automatically starts downloading. While doing that process, the xbox one takes all the internet, and other device cannot use internet properly. It gets extremely slow. I'm wondering on how to do that on PC.
There is no way to allow your laptop to use all the bandwidth (data) on your network via the laptop. All of that is managed by your router.
If you have a fairly decent router, you may be able to find something called "QoS" which stands for Quality of Service. QoS will allow you to select a device on your network, and then the router will automatically make sure that the device you selected will get the best performance. But there is a tradeoff. All of the other devices on the network will lose speed. This is because your laptop will now be taking priority over everyone else's.
Something else I would like to mention is that it sounds quite strange for an Xbox to hog all the bandwidth on your network. Usually it will only do that if it is downloading an update, or updating a game. A quick remedy for this would be to turn on the xbox late at night when no one is on the network, and allow it to do it's thing. As long as the files aren't too large, it shold be done by morning and should no longer use up all your bandwidth.