$ sudo apt-get update
$ sudo apt-get install remmina-plugin-gnome 

remmina-plugin-gnome is installed in your system.

Make ensure the remmina-plugin-gnome package were installed using the commands given below,

$ sudo dpkg-query -l | grep remmina-plugin-gnome *

You will get with remmina-plugin-gnome package name, version, architecture and description in a table

remmina-plugin-gnome package basic information: