You don't have a ROKU TV, which is a television set from any of several manufacturers which has Roku capabilities built in. As such, a Roku TV has an antenna input and can tune to local channels received via antenna, independently of its Roku capabilities.
Your Streambar is a separate Roku device that plays through a conventional TV. It has no live on-air TV capabilities of its own, but your TV probably does. To stream live TV you need to locate streaming apps that include live TV feeds.
If you are located in a country where The Roku Channel app is available on your Roku, scroll down its home page to the Live TV section where you can access about 40 live ad-supported stations. Some others like Pluto, Tubi, VUDU, and STIRR also have live TV feeds, although there may be some channel overlap.
For your local broadcast stations, if you live in an area serviced by Locast, you can get them via the donation-supported Locast app. Otherwise you'll have to subscribe to a paid service that includes your locals, like Hulu + Live TV, YouTubeTV (currently accessed on Roku through the YouTube app), Sling, Fubu, and AT&T TV. Before subscribing make sure the service has the local stations you want.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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