Want to create a forum like this.

[RKTking]

Where would I start if I wanted to code a forum like this one using MYSQL and PHP?

[simonbrahan]

If you just want to run a forum, you'd be better searching for ready made forum software and learning some HTML / CSS to tweak it to your needs.

If you really want to build one, you'd have to start by learning PHP and a database system - MySQL as you mentioned is a common one. For learning PHP, I point people at PHP The Right Way. I'm not sure of any standout resources for learning MySQL, you'll have to search for that yourself.

[Strider64]

Another good resource is https://laracasts.com/series/php-for-beginners