The Facebook Page Plugin widget lets you display a Facebook Like Box within a widgetized area of your theme.
You can set it up by following these steps:
- Go to Appearance → Widgets in your WordPress Dashboard.
- Drag the “Facebook Page Plugin (Jetpack)” widget into one of your active sidebars.
- Fill out the options, including your Facebook Page URL.
- Click “Save” to save your changes.
The widget options will look like this:
NOTE: the Facebook Page Plugin widget will only work with Facebook Pages, not personal profiles. This change was introduced by Facebook with the update to their Graph API (v2.3) in June 2015.