Google Drive for Desktop allows you to access your Google Drive files within your Windows File Explorer the same way you would access the Z: drive.

It allows you to browse and launch files stored in your school Google "My Drive" and Dene Magna Google Shared Drives

However, if you are not seeing "Google Drive (G:)" in your file explorer you can launch it and login by clicking "Start Menu (Windows Icon at the bottom on taskbar) > Search for "Google Drive" 

Select Google Drive 

When you run the application, you will be need to sign it

When you click Sign In you will be taken to the google account sign in screen, same as if you were logging into your Gmail account

Sign in with your work email address and password and authorise any permissions needed  (note this will only be needed the first time)

Once signed in you will see this box come up in the bottom right corner of your screen which is how you know its done it correctly

You will then be able to go to your documents in file explorer and under the list you will see "G: Google Drive"

On your home device browse to https://www.google.com/intl/en-GB/drive/download/, download and install. 
You can then follow the instructions above to launch and use Google Drive (G:).  You will need to login with your school Google email address and password.