You can look at many games in informators, this is my first defense I
prepared and you will notice that your oponent have to make many
mistakes for you take advantage, if you are starting playing chess is
better prepare something a little more agressive like sicilian, because
if your oponent make a mistake could lose the game immediatly.
This also can increase your tactics, is better start playing tactical
openings.
The enciclopedia has all variants and how to response to some moves
that are not in the line, but you have to memorize that and is a litte
hard, then you need to undestand the idea and plans of the opening
you are playing, so is easier for you to play it, and looking grand
masters treating this openings helps you a lot.
With all the different openings and variations you will never be able to
force an opponent to make a certain move. However if you play black
you can influence the type of game to be played. White moves first,
but black dictates the style of play, be it a game of control of the
center or the more accepted strategy of letting your opponent "think"
he has control of the center and you attack it from the flanks. Never
rely on just one opening, otherwise once he deviates you will be lost
