How to replace parameters within the nested folder of projec

Question

I'm creating a visual studio project template using c# on visual studio 2013. I followed the https://www.jayway.com/2015/03/13/visual-studio-how-to-create-a-solution-template-with-multiple-projects/ steps.

1. I created project template with a vsix project.

2. Then I created a Custom Template Wizard vsix project then Connected the Wizard to the Custom Template then added the Custom Parameter to the Template.

3. My projects are placed within the projects folder into the project template solution.

Now , my target is to replace some of the parameters of the files which are placed within the projects folder (files of project containing multiple projects) i.e in the nested folder of the project template solution, based on the input from the wizard.

Any help on above point will be appreciate and helpful.