This series will teach you how to set up a JavaFX game with a basic starter file, and how to use that to create a platformer. You will learn how to implement animation, music, gravity, collisions, reading/writing levels to a text file, etc.
This GitHub repository has tutorial documents that will guide you through each lab in this tutorial series, as well as art, code, and music assets.
Useful links include the Utility Methods file and Oracle's official JavaFX API Reference. Refer to these if you are ever confused about which methods to call.
Start the tutorial series with Part 1, which discusses the creation of a starter file with a frame loop, JavaFX integration, and keyboard input.
In Part 2, you will start creating classes for the player, enemies, and terrain.