Why am I seeing this?

Fixed - thanks!

In the main application toolbar you will find a “Group Mode” 3-way toggle. Currently you have the third option “Outliner” selected, which is what you’re looking at in the main viewer. The middle option is “Corkboard”, which you’re probably familiar with, and the first option is “Scrivenings”, and I’m guessing that is what you mean when you say you want to “open the full manuscript”, it’s the one that shows the text content for the selected folder and all of its child items.

View modes are described in the interactive tutorial in step 7, and there are some further pages beyond that which describe the individual views.

Thank you!