A. To use Xtream IPTV on Firestick, you can sideload the app. First, enable 'Apps from Unknown Sources' in the Firestick settings under 'Device' > 'Developer Options'. Then, download the 'Downloader' app from the Amazon App Store. Open Downloader, enter the URL for the Xtream IPTV APK file, and download it. Once downloaded, install the app and you should be able to use it on your Firestick.

B. Alternatively, consider using an Android emulator on your Firestick, such as the 'Nox App Player' or 'BlueStacks', which can run Android apps including Xtream IPTV.