Connecting an XBox 360 to a windows 10 PC

Make sure the Xbox 360 is powered on. 

On Windows 10, RIGHT-click your network icon next to the clock (either WiFi waves or a computer screen with Ethernet-cord icons) and open the network and internet settings.

Be aware, that I'm using a German Windows 10, so my translation of the settings might a bit off, but I hope you'll find what I mean. 

In the Network and Internet settings, find the "Network and sharing center" further down on the "Status" screen. Click on that. 

In the new "Network and Sharingcenter" find "Change advanced sharing settings" on the left. 

On the bottom, expand the section "All Networks".

Under the section "Media Streaming", click on the "Select Media Streaming options..."

If necessary, activate media streaming. 

It should now show you a list of devices in your local network. On the list should be your Xbox 360, if it's powered on. 

Allow the Xbox 360 to access your shared media. 

Now open the start menu and type "Windows Media Player". Open the Windows Media Player Desktop App. 

Check that your videos appear in the Media Player's Media Library. 

If not, make sure that the Media Player knows where your videos are stored, if they are not in the default location (C:\Users\[Your Username]\Videos)

If your videos are in a compliant format, they should now be able to be streamed to your Xbox 360. 

If you are talking of movies you have purchased from the Films & TV app, then you do not need to do anything, as the Xbox 360 and Windows 10 have their own Films & TV app, just log in on the device you want to watch those movies, and then launch the app. Your movies should show.

If you have movies that you have purchased elsewhere and using the app to watch them. You only need to turn on the play to option on the xbox 360, then when you start the app on Windows 10, start a movie, then in the bottom corner of the film there will three dots. Select it, and choose cast to device. The Xbox 360 should show up. select it, and it should play on your console.