I am IN the box! Meaning, I am inside the box! I am ON the box! Meaning, I am on top of the box! The words in and on do also have different meanings but generally it is the ones that I provided for you above!

IN 1. to indicate inclusion within space, a place, or limits): Example. I was walking in the park. 2.indicate inclusion within something abstract or immaterial Example. I work in politics. 3. indicate inclusion within or occurrence during a period or limit of time Example. I will be done in ten minutes ON 1. supported by or suspended from: Put your package down on the table; Hang your coat on the hook 2. so as to be attached to Hang the picture on the wall. Paste the label on the package. 3.so as to be a covering or wrapping for: Put the blanket on the baby. Put aluminum foil on the food. 4. The television set was on. Both very frequently used as prepositions, adverbs,adjectives