Unable to install Gazebo Plugin for Simulink co-simulation

I am following the instructions in this page to install Gazebo Plugin - https://nl.mathworks.com/help/robotics/ug/perform-co-simulation-between-simulink-and-gazebo.html

I was unable to understand where to run this command packageGazeboPlugin

and where to download this file zip file to unzip and put it inside a path like the statements mentione below -

"Copy the GazeboPlugin.zip to your Linux machine that meets the following requirement:

Unzip the package on your Linux platform, for this example we unpack to /home/user/src/GazeboPlugin."

Please let me know