Keyboard not working

Look at link video this keyboard turn on when i connect first work keyboard and connect mechanical keyboard at this same time and on old keyboard i click numlock then mechanical keyboard turn on and good work.

depends on the keyboard you are using, some keyboards use the same circuit for multiple keys and then that prevents this, and if it did work then it could be the keyboard going faulty or the keyboard controller.

is this on a separate keyboard or a laptop keyboard.

Did this keyboard previously work? What keyboard is it?

It will work straight away for text input during messaging and the likes.

Every time the Xbox would show a virtual keyboard on the screen for text input, the keyboard will work.

As for games, the game has to be specifically made to support keyboards.

Not all games are able to use keyboards.

For example Fortnite and Minecraft are popular examples for games that work with an USB Keyboard and USB mouse.

So, is this for all Xbox app/Microsoft Store games?

May I know if you tried reinstalling your keyboard/usb driver?

Press Windows key + X , Select Control Panel > Click Troubleshooting > Click on View All > Click on Hardware and Devices Troubleshooter > Click on Next button to run the troubleshooter and try again

Also, check for windows updates:

Open Settings, click Update and Security and then Windows Update;

Click Check for Updates;

Click the Download and Install Now option, if available (Install optional updates as well)

Also, check the Microsoft Store for any updates on the Xbox apps and its services and update everything too.

Did you already tried running the SFC tool? Didn't work?