Page ID for custom index page

I am trying to add a widget to my home page. In the instructions for doing so, I am supposed to enter the page ID of the page where I want the widget to appear. However, I can’t find the page ID in the “pages” section of the dashboard, because the home page is custom. How can I identify the page to show the new widget section on?

The support for where I bought the Genesis child theme is unresponsive.

Thank you.

The page I need help with: [log in to see the link]