Most kiosk modes are made for business and come with business pricetags or subscription costs. I'm trying to make my Android TV device (Dynalink DL-ATV36) just auto-launch into Duo on powerup. It doesn't matter if someone can "accidentally" quit and drop back to a home page - it's personal use for a somewhat less savvy family member who can just re-launch/power cycle in the event of an oops.
Are there any launch-from-start options / home pages out there?
I am not that sure about whether android Tv supports app pinning and kiosk mode. On an alternate solution, have you tried Button Mapper apps for your Tv. You can map Duo to a remote button and family member just needs to tap any of the button in remote to launch duo.
https://play.google.com/store/apps/details?id=flar2.homebutton&hl=en_US&gl=US
https://mrnoob.net/customize-unused-buttons-on-android-tv-remote/