Yes,you are eligible to give MSc life science entrance exam.

Eligibility for the exam are:

Bsc(H) after 10+2 with major/honours in life sciences and any other related life science discipline/Biosciences/Botany/Zoology.

At least 50 percent marks in aggregate or an equivalent grade for General candidates and 45% marks for SC/ST.

Hope this helps you.

Hello,
As you mentioned that you're in second year of your undergraduate studies and since yours is a 3 year program therefore you'll be able to appear for MSc exams for admission in different institutes in your 3rd year only.
And you can apply for any course you want to study further(few exceptions) including life sciences.

So, prepare hard you have plenty of time for it.
All the best!