Anyone know how to code lua?

Lua isn't too hard. Compared to something like C++, it's a baby language. The heart of learning to code is understanding the logic. Once you start to think like a programmer and know a few ways to complete common tasks, coding is just referring to the GMOD Wiki and constantly testing your code. You won't be able to code the sort of stuff found on the GMOD store within days, but you'll pick up stuff slowly. Keep at it and you'll do fine.