Hello Meghna. For Undergraduate and Diploma courses in the Paramedical sector:

• You must have passed 12th from science stream with biology from any recognized board with at least 50% marks.
• For the diploma courses, there is no minimum percentage as every college has its different criteria about the percentage
• Some colleges even accept admission on behalf of the percentage obtained in board exams
• Most colleges have entrance exams and offer admission as per the marks scored in these exams.