If you order a new Kindle directly from Amazon, it usually comes already registered to your Amazon account, so when you get it all you have to do is charge it up to get started reading.
If you buy a Kindle from Best Buy, eBay, or some other retailer you’ll have to manually register it to your Amazon account to get your Kindle books to appear.
You can still use a Kindle that is unregistered, but it will only works with sideloaded DRM-free files, and not all the features will be available.
Once registered you can shop for and download ebooks from Amazon, and the books will be available across Amazon’s other devices and apps as well.
How to Register Kindles
Registering a Kindle is a simple process. Just tap the Menu icon in the upper right corner on the Kindle’s homescreen and select Settings.
Then tap My Account from the list. If you have an Amazon account just enter your info to register. If you don’t have an Amazon account you have the option to create one. Just follow the onscreen directions and your Kindle will be setup and ready to go in no time.
Deregister Your Kindle
You should always deregister your Kindle if you are selling it or if your giving it to someone else. Or you can factory reset your Kindle to restore it back to factory settings (that will also deregister it from your Amazon account).
To deregister a Kindle, tap the Menu icon in the upper right corner on the Kindle’s homescreen and select Settings.
From there tap My Account then select Deregister Device and then confirm it.
If you lost your Kindle and can’t find it or if it no longer works, you can also deregister Kindles from the Manage Your Content and Devices page at Amazon.