What is the ruling on setting a specific time to make up missed prayers spanning four years, given the presence of free time for studying and exams, and what is the ruling on being lazy about making them up? Is that considered hypocrisy?

Limiting the make-up of prayers to two days' worth per day is a view held by some Maliki jurists for those who have other engagements. However, whoever is able to make up more than that without hardship must make up as much as they can.

The Holy Quran describes the hypocrites as being lazy in prayer: "Indeed, the hypocrites [think to] deceive Allah, but He is deceiving them. And when they stand for prayer, they stand lazily, showing [off to] the people and not remembering Allah except a little." (An-Nisa: 142). It is disliked for a Muslim to stand for prayer while feeling lazy.

Therefore, one must repent to Allah and strive against their self to avoid being sluggish about prayer in the future.