In your web browser navigate to the page you want to make edits to.
Example: http://techartorg.github.io/python3/python3-snippets/latest_installed_program
At the top right of the page you will find a Edit on GitHub
link.
Click that link!
This link will take you to the GitHub page for the corresponding Markdown file.
At the top of the page you will see the full path to the file you want to edit.
Example:
content/pages/python3/python3-snippets/latest_installed_program.md
make devserver
start peldev.bat && start pelserv.bat