Windows is very outdated or missing App Installer.
: If you encounter error 0x80073CF3 , it indicates that the application you are trying to install is missing this specific framework dependency. Summary of Latest Versions Get started with WinUI 2 for UWP - Microsoft Learn microsoft.ui.xaml.2.8 appx download
For adding the framework to a Windows image (WIM): Windows is very outdated or missing App Installer