Make sure your Roku device supports AirPlay and is updated to the latest software
Make sure your iPhone, iPad, or Mac is connected to the same Wi-Fi network as your Roku
On Roku, go to Settings
Select Apple AirPlay and HomeKit
Turn AirPlay On
On iPhone or iPad, open Control Center
Tap Screen Mirroring
Select your Roku device
Enter the AirPlay code shown on your TV if prompted
To AirPlay from an app, tap the AirPlay icon
Select your Roku device
To stop AirPlay, open Control Center and tap Screen Mirroring again or disconnect from the AirPlay menu