If you have an Apple TV or AirPlay 2-compatible smart TV, you can use Screen Mirroring to see the entire screen of your iOS device on your TV.
- Connect your iOS device to the same Wi-Fi network as your Apple TV or AirPlay 2-compatible smart TV.
- Open Control Center:
- On iPhone X or later or iPad: Swipe down from the upper-right corner of the screen.
- On iPhone 8 or earlier: Swipe up from the bottom edge of any screen.
- Tap Screen Mirroring.
- Select your Apple TV or AirPlay 2-compatible smart TV from the list. Need help?
- If an AirPlay passcode appears on your TV screen, enter the passcode on your iOS device.
Your TV uses your iOS device’s screen orientation and aspect ratio. To fill your TV screen with the mirrored iOS device screen, change your TV’s aspect ratio or zoom settings.
To stop mirroring your iOS device, open Control Center, tap Screen Mirroring, then tap Stop Mirroring. Or press the Menu button on your Apple TV Remote.
For more information click here: https://support.apple.com/en-us/HT204289