Here, you can drop a .nes file and start playing a NES game!
NOTE: You must use a legal dump or a fan‑made NES ROM.
Here are the valid ways to obtain a .nes file:
Dump a real NES cartridge using a hardware dumper (such as INLretro, Kazzo, or other NES dumping tools).
Dump NES Virtual Console games from a homebrewed Wii or Wii U using homebrew apps that extract the ROM to your SD card.
Use homebrew NES games, which are free and legally distributed by their creators.