How to Open and Use Multiple Desktops

To access the ability to open multiple desktops in Linux Mint,
press and hold the left Ctrl key and the left ALT key then press the UP Arrow key.

This will open the screen showing the 4 available desktops you can use.

You can now drag (with the left mouse button down) any open program window that is open on the Main desktop onto any of the other 3 desktops that are available and "drop" it onto that desktop.

You can also click into any of the desktops and you will now be "inside" that desktop. Here you can open anything that you want to work with on this desktop.

To switch back and forth between the deskops you are using, just press the CTRL-ALT-UP Arrow keys again and the available desktops come up and you can click onto any one that you now want to work with.

One additional tip is that when you have the multiple screen option open and you want an additional workspace/desktop, you will see on the right side of the screen a (+) sign. Clicking on that will create an additional workspace for you.

This can be very handy if you have a big project going and lots of programs and windows open. You can orgaize them onto individual screens to work with and quickly switch back and forth. Additionally, you can copy/cut and paste between the desktop windows as well