fceux software package provides all-in-one NES/Famicom Emulator, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install fceux
fceux is installed in your system.
Make ensure the fceux package were installed using the commands given below,
$ sudo dpkg-query -l | grep fceux *
You will get with fceux package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Games |
| Package | fceux |
| Version | 2.2.2+dfsg0-1+b1 |
| Description | all-in-one NES/Famicom Emulator |
| Sub Section | Games |