Crisis Core: Final Fantasy VII/00: Prologue
After starting a new game, you'll see a stunning cutscene showing Zack Fair (the main and controllable character) jump onto a moving train, and take out a bunch of soldiers in stunning fashion. Once the cutscenes have ended, you're faced with a bunch of soldiers that you have to take out yourself.
Fortunately, you get a brief explanation on the controls of the game before you start. Once you've finished reading, take out the Sentries by either Attacking, or using the elemental spells Firaga, Blizzaga and Thundaga. If you prefer physical attacks, then use Assault Twister, a wide reaching physical attack that will hit lots of foes at once. This is also an opportune time to get used to dodging and guarding enemy attacks, as even if you do get hit, you only take 4 damage at the most.
Of note is the spinning slot machine in the top left hand corner, called the DMW (Digital Mind Wave). This device allows you to level up yourself and the materia you have, as well as summon and perform powerful physical attacks. However, this all depends on whether it matches up three of the same slots. In Crisis Core Reunion it will be presented to you in the next fight.
After defeating all of the enemies, you will be prompted to go up the stairs, which you will do in a cutscene, to face the first boss of the game.
After the boss is defeated, a cutscene will start, and the chapter will end.