B.Sc Nursing is 4 year undergraduate studies and those who have completed their HSC with PCB as compulsory subjects are eligible to apply for the course.
Many universities conduct their own entrance examinations and many admit students based on their 10+2 score.
To know more about B.Sc nursing check the following page,
"B.Sc Nursing: Full Form, Courses, Admission Process, Subjects, Fees, Career Options | Careers360" https://www.careers360.com/courses/b-sc-nursing/amp
Hope this helps you.