How do I stream to my Sony TV?

Stream what? It depends. Are you referring to content as available from Apple and the Apple TV app?

All the ways to watch in the Apple TV app - Apple Support

What is your model smart TV? Select newer models may support the Apple TV app natively among the TV’s smart apps, or may support AirPlay. Else you may connect an external HDMI streaming device that supports the Apple TV app or AirPlay.

List of Apple TV app-supported smart TVs and third party streaming devices - Apple

Get the Apple TV app or Apple TV+ app on your smart TV, streaming device, or game console - Apple Support

Users may download the app from the app repository (e.g. Play Store) as provided by the TV manufacturer. Search for “Apple” there.

Apple TV app user guide for smart TVs and other devices - Apple Support

Sign in to the Apple TV app, through the in-app Settings (sprockets wheel icon) with your Apple ID account, same as on your iPhone.

To stream content that isn’t available in the Apple TV app, you may use AirPlay to stream from your iPhone. Support may differ by app/streaming service/content provider. AirPlay support may be available on select newer models smart TV. AirPlay support may be available from external HDMI streaming devices, including the Apple TV box.