Hello, thank you for reaching out to Microsoft Q&A.
1
Enable Camera Permissions.
- Go to Start > Settings > Privacy & Security > Camera.
- Turn on 'Camera Access' and 'Let apps access your camera' toggle.
- And, make sure you have enabled permissions for the camera app.
2
Reinstall Camera Drivers.
- Open the Device Manager.
- Expand the arrow next to Cameras.
- Right-click your default camera driver, select Uninstall device, select the Attempt to remove the driver for this device check box, and then select Uninstall.
- Once uninstalled, restart your PC.
- Open the Windows camera app and see if it's working.
If you're still experiencing issues, type msinfo in the search bar on the taskbar and press Enter. Then, post a screenshot of the resulting dialog box.