Dear Aspirant,
If by zero you mean that you have no Idea about the syllabus, no idea about any of the topic from 11th and 12th from Physics, chemistry and Mathematics, then you may not be able to cleatr the JEE advanced exam in 8 months. However, if you have certain basic knowledge in these subjects at +2 level then you certainly can crack IIT-JEE( JEE Advanced exam).
Follow these steps and check out the links in the end:-
1. Check out the syllabus and structure your preparation, made a plan on how you're going to cover the syllabus.
The best thing to help you in this is coaching material from some good institute. They have their material prepared according to the need of the Exam.
2. When the plan is ready,make a schedule. Remember timetable matters a lot for this one year. Be ready to give at least 6 hours per day for the preparation.
3. Solve the questions from question banks and previous year JEE papers.
4. Repeat these steps. Follow --> Learn --> practice.
5. Also keep on revising the stuff every third week. It is also a very crucial step in your preparation.
Thank you.
Links:-
Comment if you have any doubts.