1:If the player dont find the key- i mean Food for the box, an line will appear leading to the correct food to get past the rooms, only 3 chances
only this hint :/... ill think of another some time
Seeing that there are only three items you can put in and that all of these items disappear once you put one item into the box... I don't think that a line that tells you what the items are is necessary.
It's part of the gameplay to interact with everything in the room - Making it too obvious would take out the fun imo^^