To change your screen resolution when using multiple monitors

[Guest]

Hey I went onto Help and Support Center on control panel because i need to
change my screen resolution and this is what it says:
[[1).Open Display in Control Panel.

2).On the Settings tab, click the monitor icon that represents the monitor
whose screen resolution you want to change.

3).In Screen resolution, drag the slider to set the resolution you want to
use for the selected monitor, and then click OK or Apply to view changes.]]

But once I open display in Control panel,I get stuck because I have no idea
what a multiple monitor is and I don't know what a monitor icon is.I'm sorry
if I'm dumb...that's because I'm kinda new to computers but please help

 

[Guest]

first multi monitor is when you have two monitors connected to your pc, i
guess you have only one connected. right click your desktop (anywhere) click
propeties, then settings. just move the slider you see to the left or right,
depending on what size you want things to be.