Many workstations are delivered and set up with two monitors, or a laptop and a monitor. You can manage how content is displayed on these monitors by change the settings.
To start right click on you desktop background in an area that is free of icons and you will get this menu:
Choose screen resolution. It will bring up the following menus.
Here you have many options. If you click on Identify in the top panel, it will flash large numbers on your monitors telling you which is 1 and which is 2.
To use both displays as one really large screen click Extend these Displays under the "Multiple displays" drop down menu. You can drag and rearrange the monitors in the top panel to change the order.
To have your icons appear on a specific monitor, select that number monitor and then find the "Make this my main display" checkbox.
To see the same exact thing on both screens, you can instead choose "Duplicate these displays"