Go to the "Cover scheduling" tab, click on the arrow to the right of "Events" and open the "Exams" window, which is also available to you without the "Course scheduling" module.
The window has two parts. In the left part of the window you see a list of all exams of the selected time range. Use the date fields for defining the time range of the exams. You can quickly shift between your self-defined time range and the total school year by clicking on the <Total school year> button. Additionally, you can restrict the view to single classes via the selection fields of the windows' toolbar.
In the right part of the window, you can create exams by clicking on the "New exam" button and start with entering the data of the new exam. All details on the "Exam" window can be read up in the manual on course scheduling in the chapter "Exam scheduling | Exams window". If in the course scheduling manual, the term "courses" is used, this includes all lessons, as well. Additionally, you need to keep in mind that exams you enter this way need to be activated before any exams, and substitutions and cancellations triggered by them are shown.