To hide any page or chapter table of contents, you can follow these steps:
Open the chapter/page in Atticus.
Click on the Cog icon located at the top right corner of the content editor (directly to the right of your chapter/page title) to access the chapter level options.
In the formatting options, select the 'Hide in Table of Contents' option.
You can learn more about utilizing the Chapter Options Menu to set additional preferences for individual pages/chapters in this tutorial: https://www.atticus.io/how-to-format-your-book-with-atticus/