You certainly are. If you have no previous experience of developing a website with a database and forum you are about to hit a massive learning curve.
Start by registering a suitable domain name, and having it hosted somewhere. There are hundreds of domain hosting companies out there, and at 19 years of age I'm guessing money may be tight, so shop around before taking the plunge.
If you're really serious about this we'll provide you with plenty of advice and encouragement, but be warned - you are in for a great deal of hard and sometimes frustrating work. If you really know your subject in depth you are off on the right foot, but don't anticipate earning anything at all from your project until you are getting a considerable volume of traffic on the site.
Register a domain name, and come back for advice on the next steps.