To do this on your Chromecast with Google TV home screen, choose Settings System About System update.
You need to access your Chromecast updates from your TV. If you have a Chromecast with Google TV, the update doesn't appear in the Google Home app. The update is done automatically as part of the setup, so you don't need to do anything.
To enjoy the latest features available on Chromecast, your device might need to update to the most recent software version.
