If you want to play Pokemon Go on a Kindle Fire tablet, you will need to factory reset the device which will wipe all of your data. If there are pictures, videos or game save data (Minecraft Maps) on the Kindle, you will want to follow the instructions below to back them up:

• Connect your Kindle Fire HD to a PC via the included USB charging cord.
• Open a windows explorer window and find the “Fire” drive under My Computer (This PC)
  
• Backup the entire contents of the device to your local PC if you want to be safe, or if you’re confident you only need certain data, copy only the specific folders you need: (The “DCIM” folder typically stores all photos/videos taken by the default camera, The “Games” folder usually stores all of the game data for Amazon App Store games, and the “Android” folder will contain play store apps from an existing installation. Some apps will install data into their own root folder, so if you’re not sure what you need, just back up everything. Also, the internal storage of the tablet will show up separate from any micro SD cards attached)