What subjects to study in high school

The basics and biology and biology-related courses.

Check with the Colleges which interest you and see what they are requiring.

And, of course, volunteer in animal-related facilities.

What's percentages do I have to pass my subjects with

To get into College in a very competitive field? The highest grades you can get, probably upper third.

Again - check with the Colleges.

Passing rate requirements in high schoool

Please use full sentences - I don't know what you are asking.

This is an International site. I have no idea what grades you need in your area to graduate from high school.

You will not get into College, particularly for zoology, if you do not have good grades. As I said - upper third.