I am also very new (6 weeks) at this game.
My suggestion is to go to the GWX download site & download and read through the GWX manual.
This is the most well done manual I have ever run across. It has a wealth of background Sub/WWII information that will help in your thinking as to why & how the game is played.
I had to read it through twice before things started to make sense, but it was well worth it.
http://www.subsim.com/radioroom/show...ht=differences
This game has a very big learning curve (for me it's double that) so the more that you know about the history etc the better
Enjoy...