You can use AirPlay to stream or share content from your Apple devices to your Apple TV or AirPlay 2-compatible smart TV. To mirror you iPhone, iPad, or iPod touch to a TV:
° Connect your iPhone, iPad, or iPod touch 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 with iPadOS 13 or later: Swipe down from the upper-right corner of the screen.
On iPhone 8 or earlier or iOS 11 or earlier: Swipe up from the bottom edge of the screen.
° Tap the Screen Mirroring icon.
° Select your Apple TV or AirPlay 2-compatible smart TV from the list.
° If an AirPlay passcode appears on your TV screen, enter the passcode on your iOS or iPadOS device.
To stop mirroring your iOS or iPadOS device, open Control Center, tap Screen Mirroring, then tap Stop Mirroring. Or press the Menu button on your Apple TV Remote.
(This how-to is based on my experiences and info on Apple’s support pages.)