If you are looking to install Android TV on a non-certified ARM device (like a Raspberry Pi or an unbranded TV box), consider these options: LineageOS for TV
The quest for an Android TV ARM ISO is a common journey for enthusiasts looking to breathe new life into old hardware or supercharge a Raspberry Pi. However, because Android TV is a closed-source platform licensed to specific hardware manufacturers, finding a "one-size-fits-all" installer isn't as straightforward as downloading a Windows or Linux ISO.