Go to Settings - this can be done by typing "Settings" into the search bar at the bottom of your screen.
When in settings, click on "Display".
Identify which Monitor is your laptop screen by clicking the "Identify" button
Select a Monitor that isnt your laptop screen, in this case the laptop is marked as "1", so I selected "2"
From the drop down menu, select "Duplicate on 2 and 3" - Note: if your laptop is a different number, select the option that doesn't include that number.
You will then get a pop-up asking you would like to revert your changed, click "Keep changes"
