Look at the Design
Switch back to your Apex Designer tab and take a look around.
Explore the business objects and the relationships between them. Try adding a property to an object and generating the project to see what happens.
Explore the user interfaces. Some of the pages (like home) are part of the application, you can open and edit them.
Other pages (e.g. /companies) don't exist in this project, dynamic pages are being generated on the fly based on the information model.