Need Help

[cbfoulds]

Your "basic clinic" SHOULD cover everything.

More than any other sport I know of, soccer is serious about teaching refs the rules [excuse me: "Laws"] of the game, and employing only "patched" officials.
Full answers to your questions are WAY beyond anything you should look for on any 'net forum. Overly simplified:

Yellow cards are "cautions" for certain player misconduct [which may, or may not also be a "foul"]. Red cards are signals indicating an ejection because of serious or repeated player misconduct [which, again, may or may not also amount to a "foul"]. The circumstances under which a card is issued, and of what color, are a significant part of "basic training" for soccer refs.

A direct free kick is what it sounds like: a free kick which may score a goal DIRECTLY: i.e., w/o touching another player. An INDIRECT free kick must touch a player other than the kicker before it passes the goal line for the goal to count. Again, the awarding of various sorts of free kicks is extensively covered in soccer ref Basic.