Use the following steps to complete the game.

Click the mat and get the key.
Go to the left and open all of the cabinets. Use the key on the locked cabinet. Get the paper fishing pole and cat bank.
Click the plant and get the coin, then go left two screens.
Use your coin on the capsule machine. Turn the handle and click the capsule.
Examine the capsule from your inventory and click to open it. You should get a red block.
Look at the paper that you have. Count the two red circles, four green circles, and three blue circles.
Click the safe and enter the code "243".
Get the magnet from the safe and combine it with the fishing rod.
Go right and use rod and magnet on the vase get the hammer. Smash the cat bank in your inventory with it.
Collect the coin and turn left. Use the coin on the machine and open the new capsule.
Combine the blue and red puzzle pieces and use it on the door.