Look at the title please.
Any light or some specific lights?
Any light will do.
If it’s a specific light, like a a flash light item the player uses, it might be easiest to just attach a collision box to it, and then work with the overlap event (for instance, set/remove a flag, and then use this in your animation BP).
Of course if it’s light in general, like sunlight, all lamps that are around etc. this won’t work.
Maybe you can also find more ideas here:
Is there another way? Your example seems a bit complex because im a beginner.
If it is a flashlight, create a line trace from the flashlight. Add a node to the behavior tree (if AI) that reacts to the line trace. Think of it like shooting bullets. If it’s a light like a light bulb, add a switch for which ABP the character will use.
Could you send a snip?