Hey Aparna

Well in general the syllabus for MBBS first year is quite vast may be equal to or more than class 11 and 12 combined

In thr first year three subjects are taught to you

1. Anatomy

2. Physiology

3. Biochemistry

Physiology will be easy and familiar to you as it carries portion from both 11th and 12th standard Ncert books. Same is for biochemistry. They'll just be in details.