Facebook Live was first only available to mobile devices (and Pages), but it has now expanded its services for all users to be able to stream directly from Your Mobile And desktops.
In order to start live broadcast from a computer, you will have to click “Live Video” from the top of your News Feed or Timeline, then follow the prompts to add a description and choose your audience
Facebook has also added a new feature that makes it easy to use streaming software or external hardware when going live from a computer. Users will now be able to share their screens, insert graphics, switch cameras, or use professional equipment in Facebook Live videos. 
You can go live while playing your favorite game, and add a camera to your broadcast so your friends can see your reactions to key game moments. You can also share screens and insert on-screen graphics, titles, and overlays.