You should solve the previous year papers and mock test for practive. Refer books to clear your basic fundamentals and learn concepts and formulas.

Solve as much questions as possible. You can subscribe any good website or mobile application where you can get daily quizes and mock test papers.

You

This is enough time if you give the time with quality to your preparation.

Hera are some tips and tricks to crack JEE main 2018 examination in just 6–7 months.

• Manage your time and always prepare more for chapters you are weak in, it will help you to not loose

Below are the recommended books for your preparation-

1- Engineering Mathematics- Advanced Engineering Mathematics by E.Kreyszig

2- Electric Circuits- Transient Analysis Of Electric Power Circuits by Arieh L Shenkmann, Circuit Theory: Analysis & Synthesis by Abhijit Chakrabarti

3- Electromagnetic Fields- Elements of Electromagnetics by Mathew N. O. SADIKU, Engineering Electromagnetics

There is no such stream like M.SC Zoology as it conducts for following subjects only i.e. Biology, BioTechnology, Chemistry, Geology, Mathematics, Mathematical Stats and Physics. Even zoology is not included in Biology stream as well. Kindly correct me if I am wrong.

Good Luck!!!

Engineering maths by bs great and aptitude by Nemo Singh and engineering mechanics by ss bhavikatti

These are the must read, and highly recommended CAT preparation books suggested by toppers:

-          How to Prepare for Quantitative Aptitude for the CAT by Arun Sharma

-          Quantitative Aptitude for Competitive Examinations by Abhijit Guha

-          Quantitative Aptitude for CAT by Nishit Sinha

-          How to Prepare for Verbal

According, to the new change JEE advanced will be online from 2018. You should plan your study according to the new change.

To be in top 100 rank you can follow below strategies-

Physics

Absolute clarity in physics comes from practice. Understand the basics of the subject rather than memorizing

Physics requires you to have a strong hold on concepts. Some chapters for JEE from physics have a heavy weightage given below.

Mechanics

Electricity and magnetismThermal physics

Fluids and waves and sound

Potentiometer-related experiments

Optics

Modern physics- It is mostly theoretical in this, the focus should be on understanding

Here are some of the books name for GATE 2018 Mechanical you can prefer.

Design of Machine Elements - Machine design - V.B. Bhandari

Engineering Mechanics-   Engineering Mechanics by Bhavikatti, Engineering Mechanics by Beer and Johnston, Engineering Mechanics by R K Rajput

Fluid Mechanics- Fluid Mechanics by R K

You can practice sample papers from the given below link

JEE Advanced Sample papers

There are many online sites where you can practice online test papers like-

1- Online test series from Allen

2- Simplylearnt

3- wisdom 24X7

4- TCY Online

5- Prepyouth4work

6- Toppr

7- Embibe

8- Career point