The date, time and venue will usually be announced in the lectures. However, it is the responsibility of students to check the notice boards for any late changes AND to obtain information about the exam venue and arrange to get to that venue. These are commonly of two hours duration, but may vary with subject. The number of essay choices, the number of sections the examination paper are divided into, and any restrictions on which essay questions you may attempt vary with each subject. Refer to previous examination papers.
Lecturers usually explain the exam format in the last lecture for the semester.
Unless changes are announced in the last lecture, students can assume the examination paper will follow the previous format. Re-reading your notes is not enough. Learning requires you to actively engage the material. Some students think that studying or researching is simply photocopying a lot of materials or collecting all the course handouts, and if they read and re-read that material they will absorb it. Not so simple.