Find the item you want to manage:
If you enter from “Teacher”, you enter directly via the “Syllabus and additional teacher information” link
it is best to enter from your personal page:

“My personal page” (click on your name in the top right of the IS between the language selection and the logout button) – “Classes” – small student icon on the right of the course – “Syllabus”
If you selected otherwise and you are on the course page, select “Full course information listing” at the bottom and then edit the “additional” data
The syllabus is divided into sections, in Czech and English, the texts can be formatted with html tags, the section descriptions are given for each field, more in: