This isn’t a Linux compatibility issue. You bought a device where the manufacturer told you in advance that a driver for the built-in wifi module doesn’t exist yet. It’s a product at the development stage.
So just follow the manufacturer’s recommendation from the product page: use a wifi dongle for now and pat yourself on the back for being an early adopter.
Having the device, I already tether the wifi. But it is indeed a compatibility issue: the old kernel drivers for the chip were janky and it’s doubtful how well they even worked the time. The code is apparently such a hot mess that the people who were working on it have stopped making progress. There is now skepticism that it will ever be fully functional.