Does this film cut down on sunlight? I need something to help reduce sunlight heating up a room, but I want light to come through.

This is designed to be a decorative film. It does not stop much if any heat and it's pretty clear so it still lets plenty of light into the room. You would want to look at the line of solar films we offer for a film made to stop heat. https://www.decorativefilm.com/ultrablock-solar-control-automotive-tint-films