M.Sc

It's not a bad option at all. You can do M.Sc in chemistry from correspondence at ANU. This university is UGC approved, having NAAC accreditation (Grade 'A'). So, it's good to do M.Sc. chemistry in correspondence from this university.

No, until and unless you clear all the subjects and backlogs, till then you can't go for any other course.

It's better to go for VIT as its the top private college in India and even good education. If you have appeared for VITMEE then you can take admission in VIT.

Kindly visit this link:
https://www.shiksha.com/science/course/m-sc-in-chemistry-central-univeristy-of-rajasthan-ajmer-130203

Yes, you can do M.Sc in Zoology in private mode.

Yes, you are eligible.

Yes, you have chances of getting the SVU. Please choose it in the counselling.

Yes, you can take admission in M.Sc chemistry in Learn Edutech. It is a 2 years course available here for distance and correspondence learning only. You are eligible for taking admission in it. For further information on Learn Edutech, follow the link provided below:
https://www.shiksha.com/science/course/m-sc-larn-edutech-behala-kolkata-182906

#Subjects of study:
Systematic botany
Business plan
Medicinal plant cultivation and pathology Traditional systems of medicine
Practical
Medicinal and aromatic plant
Diversity and conservation
Plant Physiology and Biochemistry Environmental Biology
Plant molecular biology and Microbiology. Practical
Phytochemistry
Cytogenetics and Plant breeding
Pharmacognosy Biotechnology
Practical
Enterprise Development
Biostatistics, Clinical trial
Pharmacology
IPR, Quality control, Product development Production technology
Practical
Dissertation
Viva voce