Hello
There are vary of courses available as diploma or certified course of 1 year and you can also done BSc witch is bechler and master degree of around 3 years each.
After the complition you can join the hospital or do private practice.
Average Salary is INR 2.5 to 3 Lakhs for betchler and INR 4.5 to INR 5 Lakhs per annum for masters.
Next Steps
check course availability and eligibility for different course as BSc nutrition and dietetics or BSc food science or health and nutrition education.
Health Tips
https://www.mindler.com/blog/dietician-career-india-guide/
just go through this link for further information.