The page where I put all my coding, do I need a new one for each level? Or specific events?
For instance if I have a boss battle should the code have it's own page?
Should each level have it's own coding?
are you talking about event sheets right?
well, all depends on what you want to do and how you want to do it. but NO, you are not strictly obliged to use many of them.
if you can get everything done by only one, is better.