It sounds like you would like to remove YouTube from Kano OS completely, so let's get it done!
Step 1
Go to Terminal, not Terminal Quest, in the app drawer.
Step 2
Once the Terminal loads, type the command:
sudo rm /usr/share/applications/kano-video.app
And hit the 'Enter' key
When it asks for a password, the default is "kano" unless you have changed it. When you type in the password it will not display on the screen, not to worry, your keyboard is still working properly.
And hit the 'Enter' key
Step 3
Reboot your kit and the YouTube app should be removed from your Kit! 🎉
Please Note: When a Kano OS update is applied to your Computer Kit, the YouTube app that you manually removed may be reinstalled. Please follow the above steps over again and the app will once again be removed from your kit.