You can strip a lot of the Amazon out of the tablet with XDA-Developers Fire Toolbox.
It’s still Amazon android, but it disables their launcher and store and enables google playstore and adds a different launcher.
After that it installs HA as per a “normal” tablet .
The Fire 8 I did this to is by far the most power efficient tablet in our home. Can last literally weeks on standby before it calls for a recharge. Worth the effort of converting if you get one in an annual sale (ours was £40)
2 YT videos to get an idea of setting it up:
