Before we touch any software, we must clarify what the keyword "3DS NAND Download Install" actually means.
You only do this if your 3DS is bricked—black screen, blue light that turns off, or a crash on boot. This process writes a NAND image back to the chip. 3ds nand download install
This process is for repairing a bricked console or migrating data to a new motherboard . Doing this incorrectly will turn your console into an irreparable electronic brick. Do not attempt this if your console works fine. Before we touch any software, we must clarify