How do I make the torches light up?

ObjectPropretiesTree -> AdditionalLights. I think it's like that. There you can add light, adjust the color, radius, position relative to the center of the object, and everything will light up.

And I also wanted to ask, how can I add music to a specific map?

Replace the music that already exists and will play in a particular location or when a particular hero appears. This is not difficult, but you need to enable the advanced editor.