You have all of the internet at your disposal for learning. If you're going to take on a project for learning purposes, it should be a project that is not widely available. I'll tell you why -
Users are coming to your site and some of the users aren't very smart, and by that I mean they use the same email, password, username for everything. So what happens is you are over here trying to learn and you make a nice little form for staff applications that goes into your database. The problem is you learned how to get the data from point A to point B, but you failed to properly sanitize the data. You have now left your database open for SQL injections, and that includes them being able to breach your database to obtain information from your users. Now you have hundreds of records - even from people who don't play anymore - that have been retrieved and their passwords, emails, etc. are released.
You should hire a real developer who already has knowledge in this area and work with them to learn. Watch them, ask questions, and try to repeat it yourself later.
Back to being on-topic to your actual question, you can easily google how to turn error reporting on in php