The Skull Canyon (NUC6i7KYK; KY for short) does not have an eMMC; you will never see a device named /dev/mmcblk0.
I believe that you are looking at instructions for installing Ubuntu onto a NUC5PGYH or NUC6CAYH (which do have an eMMC). These instructions simply do not apply to KY, however.
Ah that explains it! The instructions on the Ubuntu Developer site pertain to all NUCs. I will let them know that Skull Canyon does not have an eMMC.
This message was posted on behalf of Intel Corporation
That is correct the Intel® Skull Canyon does not have an eMMC, you can check this Intel® NUC specifications here: