ELI5: If light can't escape black holes, where does it go? Do chemical reactions still happen on/inside them? Can heat escape?

I've heard the gravity is so great in black holes, that not even light can escape. This raises a lot of questions for me. If its swallowing stars, particles, planets, etc, then surely it would be creating incredibly high intensity chemical reactions. Those usually create heat and light (i think). So if the light doesn't escape, does the heat? Where does that light go? Does it exist under the surface of the star?


Source.