Noone uploads that, because it would be useless for most people. Switch reads games from cartridge or installed app. Installation generates own structure, cartridge has it's own structure.
NCA on it's own won't be read by using those 2 methods that are only available for now. There are functions that allows to run game from NCA directly (possibly even by streaming from PC, but it requires tool that will handle communication), but idk what you would need to do to make it work (you can find related functions in ldr, pgl, ns, i can't find now which service could mount "@sdcard").