Here's some stuff you should try first: https://removeandreplace.com/2017/03/13/tv-power-light-comes-on-but-no-picture-or-sound/
1 – Be sure the component you are using (Xbox, Cable, SAT, ROKU) is turned ON.
2 – Check to be sure all cable and cords are securely connected to the TV inputs and component outputs.
3 – Make sure you are on the correct input as some TV’s will show a black screen if there is nothing connected to that input.
4 – Unplug the input you are trying to use from the TV (such as an HDMI Cable) and plug it back in.
5 – Check for signs of damage on all cords and cables from the TV to all components.
6 – Make sure the TV is not in ENERGY SAVE MODE, press the button on the remote control to go back to normal mode.
7 –...