[ZherkTG]

Hello, I've been wondering how I would go about making my website invite only. What I mean by that is when you go to the webpage you'll be greeted with a Login page and if you don't have an account you Register (obviously), but when you register on the site it asks you for an invitation code and if you don't have one you can't register. Also if at all possible I would also want to give users 3 codes they can give to other people and so on and so fourth. I have looked everywhere online for days trying to find how to do this but have come up with nothing (probably also because I'm a noob web developer), have help would be appreciated.