If you are talking about your local broadcast stations, Roku devices have no provisions for receiving or displaying local channels directly. For local channels you need a Roku-compatible version of a streaming service app the provides your local channels. Depending on where you are located there may, or may not, be such a streaming service available.
When any streaming service submits a Roku-compatible version of its channel app to Roku, it is given a checklist of the geographical regions officially supported by Roku and must specify in which of those regions its service is to be available. There also is a "Rest of World" option that may be selected to instruct Roku to make the app available even in areas not specifically supported by Roku. Roku honors these choices and will only make the channel app available where specifically authorized by the service provider.
If a particular channel is available in your region via other platforms but not on Roku, then it's likely the streaming service has not authorized Roku to enable it in your region. I would suggest you contact the service(s) about this directly. Don't be surprised the front line people know nothing beyond the content of their own press releases and do not understand that Roku is following the restrictions placed by their own service when their app was submitted to Roku in the first place.
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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