I need to add a second author so that this person can make changes to the game. How can this be done?
There is no way to collaborate real time with someone on GDevelop.
@Silver-Streak mentioned this in the forum post below.
In their words: “Unfortunately, like most game engines, there isn’t any full collaboration available within GDevelop. However, you can work as a team on different parts of the game, so long as you’re using ‘Multiple Files’ mode for your project, and use Github to sync your project between the team.”