Below i'm writing clear and precised steps to stop video play automatically on android.
- Open facebook aap on android.
- Login with registered email or mobile and respective password.
- Swipe left and you will get lots of options like this i have added screen below.
4. Scroll down and find "App Setting" click on that.
5. Then you will get screen like this that i have added below.
6. Click on "Videos play automatically" and select off.