Hi TDTZoe
I am Dave, an Independent Advisor, I will help you with this . . .
Apple do not provide the Apple Application Support as a separate download, it is only included in the ether installers, like iTunes, QuickTime . . etc.
So, the only way to add back that functionality, would be to install one of those apps, then uninstall the app, that would leave Apple Application Support on your PC . . .