Develop an app of environmental education, based on a video game for children

I need someone that knows how to develop a video game (with avatars, coins, animals, 3D or 2D features), who can make me a quotation of the app.

Awa:
At the beginning of the game, a world map will appear, showing all the oceans. The children must choose the sea they want to protect. Awa will provide general information about it and various issues related to water, marine animals, and plants. Within the ocean, there will be dead reefs, plastics, oil, and other pollutants. For each of these situations, steps and tools will be offered to clean up and restore the affected areas. By the time the users finish this, the first section is completed. When the child levels up, the sea expands, and more marine animals and plants appear. Also, new skills and/or powers will be unlocked that will serve as an advantage in the game.
The user's mission will be to restore the water, in order to save the species and chase intruders who pollute or cause any kind of damage to the sea. A completed mission will come with rewards and coins, which benefit the environment and the user. In each one of them, will come to an encyclopedia, which provides information about:
Animal species and their preservation
Marine plants and organisms: Why are they vital?
Marine pollution and prevention tips
Fun facts about potable and seawater

New islands will be unlocked throughout the game. When more missions are completed, the island will be filled in a puzzle form. If the users manage to obtain all the pieces, another island will be unlocked with different activities and challenges.