This is an authorization error, you're either trying to play on a VIP server you don't have access to or are playing as a guest (the ability to do this was removed a couple of years ago). Try turning off any VPNs and make sure you're logged in. This can also be the server's fault, wait a couple...
Roblox Studio (their development platform) is available on Windows and Mac (not Linux, unfortunately), and doesn't require any extra software. I don't even have Lua installed on my computer and it all still works.
In this tutorial, I will go over:
How to detect when a user clicks a part using ClickDetector
How to send a request through RemoteEvent
How to read the request inside of another script
Please comment if I missed anything, and without further ado, let's begin...
It's a pet peeve of mine how programming languages don't perfectly compare decimals. But what is the reason for this? A flaw with the programming language itself, or how the computer running it responds to it?