@Orrin-Woodard You'll need to use the vi (aka vim) text editor to modify the config.json file. See the File Editing on the Omega section of the project book.

There's lots of resources for vi and other command line text editors online.
See the following for an intro to vi: https://www.howtogeek.com/102468/a-beginners-guide-to-editing-text-files-with-vi/