Hard to tell at this point. You'll likely make rapid gains in the first three months as you learn pacing and suffering. After that it depends on your genetics and time for training. You'll probably need 6-8 hrs of quality training per week but it's easier if you can average 10+ hrs.
Most people test lower indoors vs outdoors for a variety of reasons so your actual FTP may be higher than 200.

The biggest factor will be whether or not you enjoy training. If you do and are an 'average' male you should be able to get to 4W/kg.

Good luck!