Is the UML class diagram correct?

Question

UML

Dean's Program.
The user of the program is an employee of the dean's office. The faculty has departments in each department there are specialties, groups study for each specialty. In turn, the group consists of students. The department has teachers. Teachers lead classes for different groups.
The user can add a group, add students to a group, exclude a student from a group and transfer a student from one group to another, add a group to a teacher.
The question is:
is the UML class diagram built correctly?
And is it right to store methods for the user of the program in the Dekanat class, or is it better to allocate an interface class for the user that would store all the necessary methods.
And is it still correct to create a static class that would store all program data in the form of static lists, or is there a better way to store program data globally.