If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
You have entered into Shooter Job Training field -2. Your task in this field is to shoot man target board in a pillar room. Man target board appears and disappears in between the pillars. In the mean time, shoot the middle spot of the man target board to get 500 points and get 100 points by shooting on rest of the portion.
Use mouse to target and shoot. Aim the man target board and shoot accurately. In each level, reach the target score to unlock higher levels. Complete each level before given time ends.