JEE Main Preparation

No, you should not take a drop of 2 years to appear for JEE Main for admission in NIT or IIT. For seeking admission in IIT, you have only two chances.

Prefer any coaching printed booklets or hend written notes, for reading and prectice questions, and ncert must read.

Organic and inorganic (P block D block) chemistry should be well prepared, they are good scoring. So, prepare it with the help of teachers. Physical chemistry is quite difficult for every average student. All the best.

Just the moment, you start thinking over the exam you preparations planning of exam has started. It needs constant attention and effort from class 11th to class 12th, but if you seriously look it into your last 6 months to 10 months preparation are more vital, as the time you study is you want to capitulate more and your complete target is for clearing the exams. So, hope you clear it with flying ranks.

If you can get good branches in other colleges, in which there are good placements go for it. If there are no such branch which you can get, then drop a year and study with full attention.

No, its not possible to apply for MBA without entrance exams.

For a JEE preparing guy, nothing is known to him about the side by side as the syllabus for the exam is already so vast that student cannot anything beside that but yes if want to do something side by side then you can prepare for the state technical university exams and nothing other than that.

BITSAT, when compared to JEE Mains, is a bit tough and not easy to crack. For it, you have to do a little extra hard work and get hands-on practice to the way they take the tests, I. e. online and time duration with lots of pressure and bonus questions etc. It's a bit different from JEE Mains so keep that in mind, go through the NCERT books thoroughly and you'll crack it.
Best of luck.

Hello,
For CSE you can go for VIT Vellore, SRM Chennai, Galgotia's, BITS, Sharda and LPU (I have not mention any government college here because you have mentioned that you don't get the good marks). If you want to know which college you can get on your rank basis then click on the link given below and watch the video till the end.
https://youtu.be/hOlit6Un7l0

You should take droppers batch.