Watching videos posted on Facebook is fun, but it’s even more fun when you watch them in real time with a group of friends. You can do this with Facebook’s Watch Party feature.
How to Host a Facebook Watch Party – Watch Videos with Friends
You can start a Facebook Watch Party using your personal Facebook.com profile on the web or through the Facebook mobile app for iOS/Android. Below are instructions for both, but screenshots are provided for the web version only.
On Facebook.com, select the plus sign (+) at the top right, then select “post” to open the post composer.
In the app, tap What's on your mind? at the top of your News Feed to open the message composer.