All page widgets appear after the Body and any Accordions.
...
- After the Body and Accordions fields, in the Basic Page Widgets section of a page, select a Widget Type then click Add new Widget.
- Choose Gallery from the Widget types
To edit or remove a Widget
If a web page has an existing Widget, scroll down to the Basic Page Widgets section, and click the Edit button to change a widget or click the Remove button to delete it.
...