This feature is not available in initial release. However it is scheduled in August 2018 release. You can read about all upcoming features at http://support.scriptmint.com/support/solutions/articles/42000039265-upcoming-features.
If you cannot wait for upcoming release and want to import all the students, you can contact us at email@example.com with your students data. We usually charge $10 per 100 student data for import You can make payment via Paypal.