Disable "over-the-air" updates to prevent Amazon from patching these modifications. How to Prepare Your Tablet
However, you can achieve "extra quality" performance and a near-stock Android experience using a powerful alternative called Fire Toolbox XDA Developers Achieving "Extra Quality" Performance amazon fire hd 8 10th generation custom rom extra quality
The custom ROM experience on the Fire HD 8 (10th generation) is compelling, offering enhanced performance, customization, and access to a broader ecosystem of apps. However, the process is not without its challenges and risks, making it essential for users to research thoroughly and understand the implications before proceeding. Replace the Amazon home screen with a stock-like
Replace the Amazon home screen with a stock-like experience using Nova Launcher or Microsoft Swift Keyboard. Debloating: Locked Bootloader
: Connect your tablet via USB and use the Toolbox's one-click buttons to install Google services and remove ads. Why no Custom ROMs? Locked Bootloader