Markdown and GitHub help resources
In order to get started, you need some basic skills in writing markdown and using GitHub.
Learn to write markdown
Learn to edit files with github
The course spec is written entirely in the
README.md file. GitHub has instructions on how to edit a file. In Step 6 of that document, "add your commit" means "save your changes to the file".
If you want to take your skills further, these resources will help.