Forestry

Both are good career option and have it's own importance in the society. You have to choose in which you have more interest or suits you the most. Horticulture is about practice of growing flowers, fruits, etc. While forestry is the study of conserving & managing forests. In both you are going to take care of nature, but which is better for you that you have to decide. By the way forestry has more scope.

Candidates who have completed 12th science with physics, chemistry and biology subjects can apply for B.Sc in forestry. It is a three years' undergraduate programme.
After completing B.Sc. In Forestry, you can apply for different exams like Indian Forest Services (IFS), Central Forest Department of Indian government, Forest Official in state forest department of the Government of India.

Just open site of any forestry college and fill all your information like name, class 12th marks, address, etc.

After graduation, you can give different government exams like forest range officer and other jobs in forest department and you can also get job in private companies with a good package up to INR. 70,000 per month.

Yes, NLSIU PG course is only available through CLAT PG exam. Otherwise, you can apply to different universities. Also, I doubt that NLSIU offers PG in international environmental law.

Hello,
All basic subjects basics like Maths, Physics and Chemistry, then some general knowledge and current affairs them some English grammar and Comprehension.