Kindle Fire has 8GB of internal storage, versus 16, 32, or 64GB on the various iPad models, but there’s a reason for that. Amazon provides free storage for all your Amazon-purchased content in the Cloud (a huge collection of online storage) so that you can stream video and music instead of downloading it, if you like.
Kindle Fire has less storage space (8GB) than some competing tablets. That amount of storage will probably work just fine for you because when you own a Kindle Fire, you get free, unlimited Cloud storage for all digital content purchased from Amazon (but not content that you copy onto Kindle Fire from your computer by using a micro-B cable).
This means that books, movies, music, and apps are held online for you to stream or download at any time, instead of being stored on your Kindle Fire.
This storage means that you don’t use up your Kindle Fire memory. As long as you have a Wi-Fi connection, you can stream content from Amazon’s Cloud at anytime. If you’ll be away from a connection, download an item (such as an episode of your favorite TV show) and watch it, and then remove it from your device the next time you’re within range of a Wi-Fi network.
The content is still available in the Cloud: You can download that content again or stream it anytime you like.