How do I Make My Executable File Communicate with Windows?

Question

I wrote a script which makes an edit to the contents of a windows folder, and turned it into an EXE function with pyinstaller. I won't go into what it does specifically but suffice to say it edits the names of files in the folder. I used regedit to have the executable directly linked in the folder menu in Windows Explorer, but I get an error that there is no app associated with the file. What can I do to make the OS communicate with the app effectively.