Question about how to power Beharbros SHOGUN ULTRA UNIVERSAL SUPERGUN

I am very confused of how to power this super gun. I know it comes with a power cable which you need to wire to power supply. I didn’t know why power supply to get so I went to the Beharbros YouTube comments and he said that it could be any atx power supply or arcade power supply. but I do not how to connect this loose power cable to power supply ?? I have no experience in wiring or anything. is there like a guide I can follow or something or is there somewhere I can buy this power cable fully built so it’s just plug and play!?!

Link to supergun: https://www.beharbros.com/product-page/shogun-universal-supergun