How to set up multiple displays on Windows 10 computers
1. Identify what kind of connections are available on the back of your computer. Depending on the system you may see VGA, DVI, HDMI or DisplayPort connections available. Make sure you only use one video cable per monitor.
If it is a desktop that has a video card, the ports directly on the motherboard will not work. You need to plug your monitors directly into the video card if one is present.
2. Connect the second monitor. If the monitor does not come on intially, try shutting down the computer and turning it back on. If you have a video card, make sure you are plugging the second monitor into the video card. Once the monitor comes up, right-click on an empty part of your desktop background and select Display Settings.
3. In the re-arrange displays section, each monitor should show with a number. Click on the Identify button and a large box will come up on each monitor that identifies which one is which.
4. Drag and drop your monitors to the appropriate spot that matches up with their physical positions on your desk, then click Apply
5. Scroll down until you reach Multiple displays. Click on the drop-down box and select Extend these displays.
Once they're set to extend, both monitors should be working individually and you can drag and open windows between them as you need. You can change which monitor is the primary by selecting your preferred monitor at the top of the menu, then checking the box that says "Make this my main display."