Short novel made for a school activity

In a world shared by creatures and humans, a poor boy lives inside a kingdom where the king loves power, plotting a mass massacre of the creatures. People protested against it leading to them being killed. The boy who met a harpy manages to escape the kingdom's rules. He seeks refuge on the creatures' side prompting them to take action. Learning about the death of the creatures' king he takes over, and he defeats the king. He takes over the human kingdom and encourages humans to live with the creatures.

idk if this is the correct outline for the plot xd
anyways this is WIP

The novel should be finished based on our school's deadline (May 13, 2024)