Like any new software, if you've never used Drupal then you'll have to suffer a learning curve... though, if you're excited about doing amazing things with it that will change the world, then this won't be an issue :) 

I highly recommend not jumping into the deep when when you're a newbie; that means - don't feel pressured to learn everything about Drupal because you have a project deadline!  Its much better to have the peace of mind going into a paid project - knowing both your limitations as well as those of the software you're using.

First step: read up; there's a wealth of knowledge over in the Drupal Handbooks and they read pretty easily.  Get cracking with Drupal terminology and try to think about examples in your life where you relate things with conceptual taxonomies, for example.  It may sound geeky to philosophize about software but once your brain understands how Drupal works, working with it will feel much more natural. :)

If you've got the time to think about working with Drupal, do it until you can't wait to play around and then its time to setup a dev server - something I'll be posting about soon!