can't figure out how a noob tells...

So how are you supposed to know what's important to what positions? I know some of them sure, but I am trying to learn the game (both RL and FM varieties) and I can't always figure out which ratings are the most important for what slots. Also is there a place that I can find the roster rules and such of the different leagues? I also of course have no idea about the rules as far as all that is concerned and I am afraid to make any move until I know those rules.

Also is there a manual for the game? I can find one if there is maybe someone could point me in the proper direction if there is.

Thanks!

Here's the link to the manual, at least

http://www.footballmanager.net/manual/

If you call up a league table (or any competition) there's a "rules" tap, which includes things like number of foreign players.

If you go to the tactics screen and click on a player on the tactics pitch on the right, you'll get a list of attributes on the left hand side of the screen, with the key ones for that position, Role and Duty highlighted.