For the MacOS, all applications are folders. From the Finder, you can right-click (or Control-click if you are using a trackpad) on the program icon and select "Show Package Contents". Be aware that Apple has started to require notarized applications, and depending on your version of MacOS, modified applications make not work after you changed them, as Apple fears that the program has been tampered with. This is an issue with recent versions of MacOS, and is not specific to my software.