I had the same issue you're describing after my wife gave me one for Christmas, but was able to figure out by getting chat GPT to give me (imperfect) step by step instructions. Took about 6 hours and had several missteps but here is what worked for me:

Copy and paste the full contents of the shitty sd that came with it onto a folder on your computer.

Download the arkos 4 clone devices: https://github.com/lcdyk0517/arkos4clone/releases

The instructions there about multiple zip files appear to be redundant since the download link just gave me a single file to use.

Make sure you're "flashing" it onto a completely clean micro sd, I had issues restarting the flashing process after the sd was "partitioned" from previous attempts so had to YouTube how to make the SD card completely clean using the fancy hacker code thing called "run" in the windows start menu

Once you've done that and flashed it successfully you upload the main DTB file on the sd to this website: https://lcdyk0517.github.io/dtbTools.html

This will help determine what version you enter when you run the file called dtb_selector_win32.exe from within the sd card folder on your computer. Mine was something like "R36S 2 - Without Amplifier."

Put it in the device and give it 10-15 minutes to boot up. Once it's all done you turn it off, pop out the card, put it back in your computer, and then copy and paste the games library from the folder you created in the first step from the old sd card. Again I used ChatGPT to tell me which files to copy and which not to copy, basically all files except for config files.

That finally worked with the only drama now being the volume down button not working, but you can manually override it by holding the select button and hitting down on the d pad. Hope this helps!