gnome-core software package provides GNOME Desktop Environment -- essential components, 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 gnome-core
gnome-core is installed in your system.
Make ensure the gnome-core package were installed using the commands given below,
$ sudo dpkg-query -l | grep gnome-core *
You will get with gnome-core package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Meta packages |
| Package | gnome-core |
| Version | 1:3.20+2 |
| Description | GNOME Desktop Environment -- essential components |
| Sub Section | Meta packages |