How would I be able to customize the Player List Name Colors?

So basically, I saw one of my friends doing this. I was pretty confused and yeah It's client but I'd want to use it. I have no Idea how to do it, I even tried to read ROBLOX api But I still didn't understand. He also was able to add custom Icons and it looked really good, Ill show examples below.

https://prnt.sc/o2lis1

https://prnt.sc/o2limx

If you know please help, Thanks.