Record the screen on your iPhone, iPad, or iPod touch - Apple Support
If the screen record option is not on your control panel,
- Go to Settings > Control Center, then tap the Add button
next to 
Screen Recording. - Open Control Center on your iPhone, or on your iPad.
- Tap the gray Record button
, then wait for the three-second countdown. - Exit Control Center to record your screen.
- To stop recording, open Control Center, then tap the red Record button . Or tap the red status bar at the top of your screen and tap Stop.