You're caught in a maze and the only tool you have are bombs. Put one down and get out of there! Do you kill all the enemies within the time frame, you get to go to the next level. Hidden under boxes and bushes are coins, boots, shields, etc. You find them if you blow up the boxes etc. Try to get as many as possible, because the more you have, the more you can buy in the store afterwards. Should you catch fire, extinguish it quickly with a fire extinguisher and you might survive.
With the arrows you move around, with the space bar you arm a bomb. The ctrl key will extinghuish you if you're on fire.