Plug in the computer to a power socket, and plug in your mouse and keyboard.

Before you plug in your monitor, check that you are using the correct port. Look at the image, and plug it into the lower one. (Outlined in green)

Flip on the power switch on the back of your power supply, then press the button on the top of the case. 

If you bought an extra WiFi adapter from Amazon, just plug it into one of the back USB ports.

Windows 11 is already installed, all neccessary drivers are installed, and all of the needed RGB softwares are installed. If you got a WiFi adapter, the driver downloads can be found here.