After the connection succeed:
For an Android device:
Tap the “Start” button in the chat area and your screen will be shared.
For iOS device:
1. Swipe up from the screen button to open Control Center.
2. Long press Screen Recording button 
(Note: Make sure to press and hold.)
*Can’t find this button?
Return to Home Page > Open Settings > Find Control Center > Tap Customize Controls > Find Screen Recording and press 
.
3. Select Remote Support in the pop-up dialogue, and tap “Start.”
4. Return to Remote Support.