You're looking for a review of Android TV 12 ISO download and its functionality. Here's what I found:
Additional Resources
Introduction
Conclusion
Most users looking for a "workable" Android TV ISO are trying to repurpose old laptops or desktops. Because Android TV is a proprietary platform, official ISOs for the x86 architecture (the type used by Intel and AMD PCs) are rare. Official Google Images : Available as Generic System Images (GSIs) ADT-3 builds
Legal note: Distributing Google’s proprietary apps (GMS, Play Store) without license is against Google’s terms. Most custom "Android TV ISOs" include them illegally.
System Update: Go to Settings > Device Preferences > About > System Update. If version 12.1.1 or similar is available for your specific model, you can download it directly.
Modern High-End Boxes:
The Installation Process: How it "Works"
If you locate a legitimate image file for your specific device, the process is not a simple installation.