The cheerful pineapple thinks he's cool and is going to prove it in Find Cool Pineapple. But while he was boasting about his coolness, someone locked him in a room and the pineapple was helpless. To pull it out, you need to open two doors and, accordingly, find two keys. There is little furniture in the rooms and most likely the keys are in one of the drawers, but each has a lock that looks like cut out silhouettes of a certain shape. You need to find objects that will definitely fit into the niches and then the box will open. And you can pick up the key and insert it into the keyhole of the door at Find Cool Pineapple.
