Reading input files via parameterized approach from cross project in a portfolio

I have a portfolio in my firm’s space. In portfolio, I have one project with all pipeline and contour and workshop app. I want to make this project something like master project. And use this master project for multiple clients seeking the same solution. For this I am trying to read the client input files from their respective client project folder via Parameterized path in master project pipeline but I am not getting such option to read client input file.

Can anyone help me with this approach or something similar with which i can achieve this concept?