Hi Himanshu,
This is likely because of one of two reasons:
- There are no request queues setup/live in your instance, you can read more on how to do this here (seems unlikely if you are expect to see options in the Request Type dropdown)
- You have not been granted permission to view the request queues in your instance. I would recommend reaching out to your system admin or the request queue owner who will be able to grant you the necessary permissions.
Best Regards,
Rich.