How can I display content from my iPhone on a smart TV?

What type of TV do you own? If it's a Roku, Fire TV, or Chromecast, consider using a mirroring app like DoCast. Just download it from the App Store on your iPhone https://apps.apple.com/us/app/docast-cast-and-mirror-to-tv/id6446948344 and follow the on-screen instructions to connect it to your TV. Ensure both your TV and iPhone are connected to the same Wi-Fi network. When your iPhone detects your TV, tap "Start mirroring" in the app to begin.

The TV Mirror and Replica apps are also good choices.

Alternatively, if your TV has an HDMI port, you can mirror your iPhone screen to your TV using a cable.

Hi there

See this for the steps on how to airplay to your television

Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support

See this link for help --> Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support