A reveal is a twist in the tail. It can be like the punchline of a joke, suddenly taking the story onto a completely different terrain (the main character wasn’t a person after all, they were a worker bee, for example). Or it may suddenly show the machinery that was driving the story. Or it may make metaphorical and magical connections between events (this is often done by “mirroring” between an event and an earlier one).
Write a short story with a reveal. You may want to work backwards from the ending, as in exercise 8