HTTPService is a method for communication with other website’s through APIs. You can’t just give it any link and have it work. The server you’re communicating with needs to have an API endpoint that it can use to send/recive information to/from to
Since pastebin allows you to get the raw text data in a url you can just have Roblox request the URL of the raw text data. So on pastebin just click the option to view the paste as raw and use the URL.
But you can’t use this on any regular website.
local HTTPService = game:GetService("HTTPService")
local url = "https://pastebin.com/raw/dvMZYx64"
local data = HTTPService:GetAsync(url)
local text = JSON:Decode(data) --This is probably not required for this purpose but is a common step.