On Roku TVs, the OTA tuner is labeled as Live TV. You are saying it's not shown on the home screen? Go into the Settings/Input (I'm going by memory here). You will find all inputs enabled and disabled. Find the Live TV input and ensure it's enabled. Again, I'm going from memory, so it might be labeled differently than I remember. My Roku TV is upstairs and I'm just not up to another climb up the stairs right now.
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