get a lens that is good for burning ants outside…now go inside your house and turn on your powerful TV. Focus it’s light on paper and see if you can burn it. Repeat with fire and with a projector.

The light from the sun has traveled millions of km already, the fraction it has to travel from the earth back up the satellite is mathematically insignificant.

Your tv isn’t powerful… use something that has a similar function, like an actual light and it can work, but it will be affected by the inverse square law since the source is right there, unlike the sun.