You need an emulator, and someone needs to build the game file to run on the emulator. We won't even get into the licensing for such.
The issue is that PC applications are very much different from Android apps, it's not easy to make a PC app work on Android because of the way they are installed on Windows. There are already emulators for NES out there, but they are of questionable legality as well so I won't go there...
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