there r options like clone ( same images on both ) or independent of each other in ur display control panel ( right click in any empty are on ur desktop to access) panel may look diff for diff video card type like nvidia intel amd. but all of them have same common properties just styled differently. u will see multiple monitor option in them.
Ur video card should support multiple monitor.
suppose one monitor is primary. u will have drag with ur mouse ur program to the other monitor to see it on that. just experiment a bit