On the main Community forum page (not sure how to get there? click Amazon KDP Support near the top left of this page) there is a link to the Help pages near the top left. Click there, and you'll find a wealth of information to get started. Spend a couple days reading everything, including the contract you would enter into in order to publish through KDP-Amazon. Amazon also has a free book you can download, "Building your Book for Kindle." After reading everything, come back if you have specific questions. Good luck!