Your K9GAG08UOE seems to have an 8 bit parallel data bus. You'll need to
- read the datasheet on the timing requirements of that, then
- you'll need to find a microcontroller that can interface on an 8 bit parallel bus (you could also bit-bang on 8 GPIO lines, but that will be horribly slow, and possibly not even meet the timing requirements), and then
- you'd design a circuit board that connects the 8 data lines of the NAND flash to that controller on the MCU, and also offers power, the read/write flags and so on,
- you'll need to be able to use the device as the flash memory it is, which would then enable you to pick an operating system (writing one sounds like a bad idea) that
- you'll need to write a hardware driver for your flash, and only then the OS could employ a file system on that device,
- you would then use to interface with the memory to give you a notion of files on that, and then
- you'd write a software for that OS that does something interesting with the memory and the files it stores.
Embedded development is not like application development on a PC or android device - there's no "driver", no "ready to be done exactly like this and that". You'll have to design all this yourself!