Is it considered a lie for a person to tell his brother to inform whoever calls for him that he is taking an exam at school, while he is at home?

Disobeying Allah Almighty in two ways: commanding to lie, and indicating that lying is a way to escape predicaments. One must repent from this, feel remorse, and resolve not to return to such an act. The brother must also repent for his lie; it was possible to use dissimulation (tawriya) and allusion.