Answer 1

It's coded in Lua.

There is an introduction to scripting if you want to see: https://create.roblox.com/docs/tutorials/scripting/basic-scripting/intro-to-scripting

Or if you want a tutorial in Lua: https://www.tutorialspoint.com/lua/index.htm
And a online compiler: https://www.lua.org/cgi-bin/demo

Answer 2

Roblox is lua