Source link : https://mykodiaddons.com/install-amazon-prime-video-kodi/
Please enable unknown sources from setting before start.
First Download Repo File by clicking here
Launch Kodi
Press SYSTEM
Press Add-Ons
Press Install from zip file
Locate and press zip file you saved earlier repository.xlordx-1.0.0.zip
Wait for Add-on enabled notification
Press Install from Repository
Press XLordX Repo
Press Video add-ons
Press Amazon Prime Instant Videos
Press Install
Wait until you see Amazon Prime Instant Videos Add-on installed message
Amazon Prime Videos is now installed and ready to use.