TISS - Tata Institute of Social Sciences, Mumbai

Yes, you are eligible for the course.

http://admissions.tiss.edu/view/10/admissions/ma-admissions/ma-msc-in-regulatory-governance/
This is the syllabus.

No, there won't be any issues for the break. Documents that may be needed is income certificate. If you need fees concession and community certificate or seats through quota, then class 10th, class 12th marksheet is required for the admission.

https://appln.tiss.edu/ For the TISS, here it is all the best for the admissions.

http://admissions.tiss.edu/view/10/admissions/ma-admissions/m-a-social-work-in-public-health/ . These are the paper you will be having for two years. Due to the emergence of health sector now the scope for public health is really high and I am not much aware of the papers from the Assam social work. But, I can assure the overall learning will be very good enough and explorative.

https://www.quora.com/What-is-the-average-package-of-a-post-graduate-from-TISS-with-his-her-MA-in-rural-development-The-course-is-from-TISS-Tuljapur
Go through link

No, it is not necessary to do the job along with studies to appear for TISSNET exam.