In a previous query, already I told you that exam pattern of PG in Sikkim Central university for geography entrance is Multiple Choice Question (MCQs) Based on OMR sheet. Earlier it was descriptive type. But now objective type only. Prospectus_2019.pdf
Common Admission Test (CAT) is conducted for Admission in UG and PG Courses. Exam pattern is
1. Exam Duration: 1 hour
2. Total Marks: 100.
Question paper will be of objective type and eight test venues namely Guwahati, Kolkata, Patna, Siliguri, Darjeeling, Kalimpong, Gangtok, Namchi and Geyzing.
So don't worry and start preparation for next year. Forms will be available next year and exam most probably will be conducted in June 2020.
For reference, you can check question papers of PG geography entrance exams of other university also.
For more information you can visit website: https://cus.ac.in/
and check link also https://cus.ac.in/images/content/dynamic/noti/2019/ADMISSION/Prospectus_2019.pdf
Prospectus 2019 of the Sikkim University for CAT exam for UG and PG and other Courses (Page no. 11, highlighted text) attached here for your reference.