This article explains how to download any video from Facebook to watch on your device at any time, without internet access. These instructions work on both a computer and a mobile device.
How to download videos from Facebook
Media uploaded to Facebook can serve as a backup if you lose the original file. To retrieve a video from Facebook that you have uploaded:
Log into Facebook on your laptop or desktop computer and go to your profile page.
Go to the main menu and move the cursor over More.