To get your PC to recognize multiple monitors:
Make sure your cables are connected properly to the new monitors, then press Windows logo key + P to select a display option.
If you need more help, here's what to do:
Select Start > Settings > System > Display. Your PC should automatically detect your monitors and show your desktop. If you don't see the monitors, select Detect.
In the Multiple displays section, select an option from the list to determine how your desktop will display across your screens.
Once you've selected what you see on your displays, select Keep changes.
You can change the resolution of your displays. However, we suggest using the recommended resolution to get the most out of your displays.