Check out the Introduction to Dashboards article to understand the basics of working with widgets.
The Facebook Widget provides the ability to embed Facebook pages, profiles, or feeds directly into your dashboard.
The Facebook Widget allows you to easily keep up with what's happening on your company's social media page. You'll even be able to click on specific posts and open them in a new tab if you want to interact with it.
The Facebook Widget can be configured to display any embed. You can use this link to easily create a Facebook embed that does exactly what you want and only takes up as much space as you allow. (Note: After you click "Get Code" you'll want to use the information from the IFrame tab.) After that, you'll just paste it into the Embed HTML area of your widget and add it!