Environmental

You can also choose Germany. In Germany, there any lots of Institute which gives free education.

In my opinion if you wants bright and calm future then start preparation for UPSC Civil services and IES exam because once you enter here you will get the time bond career promotions and other related benefits. While in private sectors you may got the more money but isolation and busy life which are the negative sides.

Yes, you can get hons in EVS. You are eligible for the same.

Yes, your rank is excellent and you can take admission.

If you have passed class 12th or equivalent level exam in science stream you become eligible. For the detailed process and criteria, please check here- https://www.shiksha.com/science/course/b-s-in-earth-and-environmental-sciences-m-s-in-earth-and-environmental-sciences-indian-institute-of-science-education-and-research-bhopal-357493?actionType=placement

Satyabama Institute or Science and Technology
Bharath Institute of Higher Education
College of Engineering
Indian Institute of Technology

I hope this link will help you:
https://www.ecologyproject.org/about/blog/colleges-with-recommended-programs-in-ecology-and-environmental-studies