What do you want to achieve? Changing a players group rank via roblox
What is the issue? I don’t know how to even start 
What solutions have you tried so far? I looked for it and couldn’t find anything about it
I’m just trying to make it so I can change any player(s) group rank from inside the game.
I’m pretty sure you can’t do that, however I have something that might interest you.
https://devforum.roblox.com/t/how-can-i-make-a-group-auto-rank-script/601608
Well unless you know how to use javascript, typescript, python or any other programming language suitable for web development then you can’t. You will need to interact with the roblox API and what you need to do requires the .ROBLOSECURITY cookie of a roblox account (the token that grants access to it) to be passed in the request and since now ip changes invalidate that cookie it has become a bit difficult to handle. Anyways just set up a web server and interact with Groups Api or just use noblox.js
You may also be able to do it within the roblox game but you would need a proxy to send requests to that api because requests to roblox.com are blocked from games as you may know and since the api is hosted on a subdomain of it it’s affected as well but passing the roblosecurity cookie through a proxy is not the best thing to do in terms of security
My reply was written in 2022 and roblox is now planning to allow requests directly to their endpoints (this was mentioned in a recent release note). The post you linked uses a proxy in the code snippet which is exactly what I was talking about in my reply.
Do you know when this will be live or where it was mentioned?
They didn’t give any ETA and If I remember correctly it was mentioned in an announcement post however I can’t find it.
In case you are concerned about passing the security cookie through a proxy, it’s relatively easy to self-host one which means you would have full control over how data is managed.
I think they’re starting to make it. Right now there’s only accept/decline group join.