Hi,
Uninstalling Notepad using PowerShell and reinstalling it helps in most cases.
Please open PowerShell (admin) and run the following commands:
get-appxpackage -allusers *notepad* | remove-appxpackage -allusers
get-appxpackage -allusers *notepad*
If the commands return any output, post the screenshot here.
(After fixing Notepad, we'll attempt to fix the Photos app.)