Are you looking for how to create a .ev3 file? Or how to program one like the files in the link?
If you are looking for how to create .ev3 files, take a look at the video in the link below.
https://www.youtube.com/watch?v=IuHaIE-auLQ
In the link, he user opens LEGO MINDSTORMS, clicks the "+" button, and saves in on the computer. They are using a MAC OS, but the steps should be very similar.
Danielle M.
Applications Engineer