It is expected that you will use the pictures and pages that are in the sample shell.
Click the
Collections tab.
In the left pane, below Sources For New Books, click the sample shell that you will use as the basis of your book.
Click
MAKE A BOOK USING THIS SOURCE.
The book is added. It opens in the
Edit tab. You see the Front Cover page.
The remaining steps you need to do depend on what kind of book the sample shell was (basic book, arithmetic and so on).
So, find tasks that match and do the relevant steps.
Collections tab tasks is a good place to start.
If the book has a Translation Instructions page, follow those instructions.