Cabinet Escape Room

There's a break and you pass by the teacher's office, from whom you got a 5 on your last test. As luck would have it, the cabinet doors are ajar and no one is inside. The teacher went out for lunch and you have a unique opportunity to erase the bad grade from his teacher's notebook. You can't resist, slide inside, and quietly close the door behind you. However, you soon find out that the teacher expected such a trick and prepared a riddle trail for fraudulent students, which will test you more than any test. If you manage to get through it, you can freely erase the grade from the teacher's notebook, which is hidden at the end of it. If not and the professor catches you in his office upon his return from lunch, you are certainly in for a scolding from the principal. The clock is ticking and you have no choice: you must start solving the tasks.