A good plot for a teen book? Can I pull it off? Can I write a book about this?

It's the year 3019 AD. There is only 4% of land above the sea left on Earth due to global warming. Life is critical and unfortunate for the people living in this time. There are roughly 600,000 people left and 80% live on large ships used as floating islands. Each ship has its own way of life and has one leader who delegates, like how countries were 1000 years ago. But not everyone is completely human. Some evolved since the second flood.

Now there is one large island that used to be known as Japan, now called Sector 9, with much smaller land forms scattered around the rest of the planet. It is the center of their world: a kingdom that struggles to maintain life, peace, reconstruction, and hope to the citizens of the watery planet.

The problem - rumors are spreading of the overthrowing of the kingdom. People are getting impatient with the way of life. They want their Earth back. There is only one thing that can preserve peace and eliminate human extinction; the prophecy of the Staff of Terrain. While the King and Queen scramble to find a plan to get the staff, their daughter, next in line to the throne, sneaks out to try and find it herself, so her family can restore the land and create habitable living conditions for everyone. When her parents catch wind of this, a throng of search soldiers go out to find her.

This is a story of a human princess who takes a journey to save the earthlings from the people of their past. She meets several evolved creatures along the way, who recognize her determination, and the idea to regain peace, and join her. She finds herself in sticky situations and goes through trails, games, puzzles, and hardships to get to her destination. As she gets closer to finding the Staff of Terrain, she finds out that an evil and sinister man wants the staff for himself so he can rule the world. It soon becomes a race against time and foe.