Install the Downloader app from the App Store or Google Play Store or Amazon App Store.
Now enable Unknown Sources in the settings of your streaming device.
Launch the Downloader on your device.
If prompted, click ‘Allow’, Click OK for developer notes.
Click OK on remote to open the keyboard and get the Kodi 18.9 version.
Once downloaded, click Install on the Kodi setup page and click Done with the installation.
Now, Launch Kodi application and click “Continue” button.
You can now enjoy the Kodi 18.9 Leia on Fire Stick.