B.E.

It's difficult to predict exactly how much your percentile can increase in the next attempt as it depends on a variety of factors, such as your preparation level, the difficulty level of the exam, and the performance of other students. However, it's possible to increase your percentile significantly with focused preparation and practice. You can aim for a 99 percentile in the next attempt by analyzing your performance in the first attempt and identifying areas where you need to improve. You can then focus on those areas by practising more questions, taking mock tests, and seeking guidance from your teachers or mentors. Additionally, it's important to maintain a positive attitude and stay motivated throughout the preparation process. With consistent effort and dedication, you can improve your performance and achieve your desired percentile in the next attempt.

It is thought that B.Tech is a superior degree and BE is not up to that level. Both are treated equally in the country, unfortunately, when it comes to foreign countries, B.Tech is treated as a vocational type of degree and rather inferior to BE
There is no difference. Historically, some institutions offered BE and master's in engineering (ME) programmes. The curriculum and the subjects offered in BE and B.Tech are all the If a student wants to choose it, they just have to look at the institute they want to pursue the degree.
In terms of Job opportunities in the market, students having either a B.E. (Bachelor of Engineering) or B.Tech (Bachelor of Technology) Degrees have equal opportunities and have equally good scope. It is in no way going to be a hindrance to good career growth.

A list of the Best Books For JEE Mains and JEE Advanced is mentioned below;
Physics:
1- NCERT Textbooks.
2- IIT Physics by D. C. Pandey
3- Problems in Physics by S. Krotov
4- Problems in General Physics by I. E. Irodov.
5- Fundamentals of Physics by Halliday, Resnick & Walker.
6- Concepts of Physics Vol I and II by H. C. Verma (Highly Recommended)
Chemistry:
1- NCERT Textbooks
2- Organic Chemistry O. P. Tandon. Organic Chemistry Peter Sykes.
3- Physical Chemistry O. P. Tandon. Organic Chemistry MS Chauhan.
4- Concise Inorganic Chemistry J. D. Lee. Organic Chemistry Morrison and Boyd.
5- Modern Approach to Chemical Calculations R. C. Mukherjee. Mathematics:
1- Maths XI & XII by R. D. Sharma.
2- Differential Calculus by A. Das Gupta.
3- Algebra Higher Algebra by Hall and Knight.
4- Calculus: Problems in Calculus of One Variable by I. A. Maron.
5- Co-ordinate Geometry: Plane Co-ordinate Geometry by S. L. Loney.
6- Trigonometry & Geometry: Plane Trigonometry Part 1 by S. L. Loney.
7- Course in Mathematics for IIT-JEE by Tata McGraw-Hill publications.
8- Objective Mathematics for JEE Main & Advanced and Other Engineering Entrance Examinations by R. D. Sharma. For more information, you may visit the Shiksha JEE Main exam page. (https://www.shiksha.com/engineering/jee-main-exam). I hope this will help you.