Yes. Any user who needs to add a category should follow the following steps. Steps to follow for Additional Endorsement in License (Flow may be differ from state to state):-
1. Visit https://sarathi.parivahan.gov.in/
2. Proceed for License related services
3. Select concerned state
4. Click on "Application for New Learners License" from "Learner's License" menu
5. Select "Applicant holds Driving License, Enter DL Number"; fill your Driving License number and Date of Birth
6. Fill up Application Form
7. Take appointment
8. Visit RTO on scheduled date, with original documents