Macro for file names

Question

Hello my name is Steven, and I'm looking for a little help with writing a macro. I want the user to hit a shortcut command and a widow will pop up asking for a file name. Then the macro will go to a central location and add each project as a subproject.
What I have is a macro that will pull 6 projects from my SharePoint, so that way the master file can be moved to a new folder location w/out losing the connection to the subprojects. The problem is that now those subprojects are still the same subprojects even if you change the name and save as. Meaning I've just created a macro that will update the files every time.
I know how to code in C++ and Visual Basic, so I was wondering if there is like a GUI that I can make pop up and say "Enter file name" (or if it can add multiple names at once "Enter file names"). Then I use that variable to search my SharePoint for that file name.