You can add widgets to a page when you are editing the page layout.
Click Edit on the page title bar, or click Edit Page Layout from the page menu. The page
is displayed in the Editing Page Layout mode.
Note: For published pages, click Edit Published
Page in the page menu, and click Edit Layout on the Republishing Page
command bar to open the Editing Page Layout mode.
Click Add Widget on the Editing Page Layout command bar. You can also click the widget placeholder with the plus icon (+).
Locate the widget in the Widget Catalog, and click the add icon
(+) to add the widget.
Click Save on the Editing Page Layout command bar.