Writing to a file is a somewhat easy task the fun part is reading from it. That stuff is a mess. If all the macros are in the same workbook you could simply Dim a variable as public/global and it would retain it's value after the code in the module ran. it would also make it accessable to everything in your VBA projects for the workbook. Unfortunetly it would lose it's value once you closed the book.
Example of a Public Dim statement (it is outside all subs and functions):
Public Features_On_Select As String
For Reading a file you can use a function like this. I didn't write it i got it from somewhere months ago.
example for writing to a file (see same comment as above):
Here is my function Path() so that you know what it is doing:
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