This is the part 1 of the animation, it's an explanation (prelude) of the planned upcoming events that will be introduced on the next parts of this history. In this 3:09 minutes animation, you can expect to see dialogues and the overall introduction of the history like Cheelai talking with other soldiers on cafeteria, Frieza talking to his dad, Frieza checking security cameras and Cheelai inviting Frieza to sit on her lap again.