Android TV 12 is primarily distributed through official manufacturer OTA (Over-the-Air) updates rather than a standalone ISO file for general consumers. However, if you are a developer or a tech enthusiast looking for manual installation files, they are available through specific official and community-driven channels.

that allows you to turn a computer into an Android TV device. LineageOS TV x86:

Be extremely cautious of third-party websites claiming to offer a "Universal Android TV 12 ISO." Android is highly dependent on for specific processors. A "generic" ISO often contains malware or simply won't boot because it lacks the drivers for your specific Wi-Fi chip or GPU.

Most DIY installations will not support Netflix or Prime Video in HD/4K due to DRM restrictions.