You only need to know Lua if you make a Lua 'mod', which is a lot simpler.
If you really want to make a C++ mod, then just Google for video tutorials/guides/references. Learning it yourself is way better then waiting on someone to teach you a bit of C++ when you both have free time.
Asking questions and getting your code inspected is a great way to improve after you've done what you can do yourself.
Have you coded in other languages before? Because certain things (like for loops and if statements) are similar across multiple programming languages.
If not, if you want to be really serious about coding, buy a book. it helps a lot.
I can give you this to get you started, but you need a compiler to see the result:
#include <iostream> //imports iostream. Very important
using namespace std; //begins your program
int main () //this is your main function. You code inside it
{
cout << "Hello World!"; //This is how you tell the computer to display something. Don't forget the quotes
return 0; //tells the computer to stop the program
} //You can take it from here NUCLEAR_FOX.