How can a class teacher view and input grades to students in their class?

The teacher's rights to view/input grades are based on official courses. A teacher with an official course created can input grades to students attending that course.

The administrator can set two modes of rights / the strict mode or the unrestricted mode.

In the "unrestricted" mode, any teacher can view/input grades to students in any class via the "advanced mode". Advanced mode to enter/view grades

In the restricted mode, a teacher can input grades to students attending their official courses or to students attending courses specifically approved for viewing/inputting grades by the administrator.

In the restricted mode, the administrator can set rights to class teachers to view/input grades. Administrator: How to set up rights in the grade book?

The class teacher can access thier students' grades by clicking grades and selecting the course:
The advanced mode appears.

Select the class.