Metroid II: Return of Samus/Phase 1

You start out next to Samus' ship. It will refill your energy and missiles whenever you enter it. You start with the power beam, long beam, morph ball(maru mari) and thirty missiles. Start by going right and down. You will soon encounter blocks that are destructible. Shoot the blocks to progress. Please note that you can aim below you in mid-air with a tap downward, and on the ground a quick tap will make you crouch. The enemies die in one hit so they shouldn't be a problem. Eventually, you'll reach a bell-shaped rock. To the right is a "save machine", to save, stand on it and press the Start button when prompted. If you were to continue to your right, then you'd very likely find a dead-end with a pit of lava. So, for now, head left. Soon enough, you should encounter the first major enemy of the game: The Alpha Metroid. It is a pretty simple mini-boss, just switch to missiles by pressing Select, and fire away at it. At any time, you can head above it to the left, and there is a secret passage in the low ceiling, leading to an energy refill. After the skirmish, you'll see (and hear!) the cavern rumble... That's your hint that all Metroids in the area have been destroyed, and the lava has receded. Head back to the bell rock, save, then continue to your right, then down to the next section.