Chuwi h10 CWI515 Android version single boot

Hello and good day I am writing from Germany and use the Google translator.
I am the owner of a Chuwi Hi10 Model CWI515
I have had the device for 2 years now and would like to install the current Android version.
Single boot without Windows. Can you give me a guide to update the bios and
a download for the latest Android version. I heard that there should be a Remix OS version.
Thanks in advance.
Greetings Thomas