Seeing a television screen in a dream symbolizes prophetic insight. It is not just the screen you are seeing, but a series of current and past events happening on that television screen in a dream.
This kind of dream appears as though one is watching a movie. It is a vision within a dream. You are receiving prophetic insights about certain events and revelations concerning people’s lives.
Related: What does it mean to prophesy in a dream?
I remember having similar dreams. I could see myself prophesying to people in their houses or a hall. Then, a huge television screen would appear on the wall. On the screen, I could see the root cause of these people’s problems and then acquire prophetic insight into how to deal with their cases.