How to make an ER diagram from a data schema in a database?

Question

Database design

Hello, please tell me how to make an ER diagram from a data schema in a database?
The photo shows a data schema in the database, do I need to make ER diagrams from it (ER-type and ER-instance)? I would be grateful for help and explanations)
(The essence of the task itself was to create a database of the department of physics, so that there was information about students, teachers, disciplines and tests (which teacher, who gave the test and for which discipline), but now they asked for an ER diagram, and I don't understand how to do it right