Where should I purchase a certificate from the University of Tokyo？

Which department of the University of Tokyo has the most difficult entrance examination?

I am a science student in my junior year of university, majoring in internal medicine.

The difficulty characteristics of the entrance examination
Science III (Faculty of Medicine) : This is the most difficult major to get into at the University of Tokyo. The entrance examination score requirements are extremely high, and the number of admissions is limited to about 100. Top students from all over Japan gather here.
Humanities I (Law School, etc.) : This is the most challenging discipline among the humanities, requiring the highest standardized test scores and the highest general entrance examination score lines

What is the average annual income of parents of students admitted to the University of Tokyo?
According to a survey on student life at the University of Tokyo, the average annual household income of parents (financial supporters) of University of Tokyo students is over 12.5 million yen. This group is the largest, and families with an annual income of over 9.5 million yen account for approximately 40%.

Where should I purchase a certificate from the University of Tokyo？What is the most difficult subject at the University of Tokyo?
The most difficult entrance examination for the University of Tokyo is the third category of science (Faculty of Medicine).
The difficulty of getting into the University of Tokyo varies depending on the admission criteria

How to purchase a certificate from the University of Tokyo?

Learning difficulty and promotion after enrollment (classified by subject)
Medical school, internal medicine department: It is said that the requirements are extremely strict. The practical training involves life and death, and a large amount of memorization and examination of medical knowledge are needed, with the aim of preventing international students from applying.
The Department of Mathematics and the Department of Physics in the College of Science: As they involve abstraction and advanced theories, they require talent and intuition. It is said that keeping up with the course progress is extremely difficult.
It is said that some departments in the College of Engineering have a large number of laboratory reports and assignments, making it difficult to obtain credits (for advancing to the next grade/graduation).