Engineering Entrance Exam

Minimum marks are basically called the cutoff marks, which is different for all category. Cutoff is high for the general category. Generally it is nearly 100, last year the cut off was very low comparatively previous years that is 81 for JEE main. For this year I can't tell you since the result is not release yet. It will be going to release on 30th April and the key will be released by 24th April. So, you are going to find your answer when the result will be released.

Yes, but WBJEE is basically for the colleges under MA KAUT.

Yes, after completing your engineering Diploma, you gets direct entry to 2nd year of engineering. Some colleges take admission through lateral entry exams like Joint Entrance Examination of Lateral Entry (JELET), Diploma to Degree Entrance Competitive exam, etc. So, you need to appear and crack these exams. Some colleges conducted their own entrance exam for getting entry. Admission procedure varies from college to college. So, you will have to contact colleges individually.

It is not that bad. If you have money and interest in the field you can take it. You will definitely gain knowledge and exposure to the culture and the latest technology. If you are just looking for the degree it is not advisable to take the course in VIT. According to the placement, VIT is not good for B.Des courses.

Yes, then also you can enter into good engineering colleges by giving their Individual Entrance Test. Some examples may be VIT Vellore, SRM Chennai.

Best books to prepare for JEE Mains are:
IIT JER Physics
Problems in Physics.

Yes, you can get any government college of your state. Be aware during the time of counseling. To get more insight about college, you can get please visit Shiksha JEE Mains college predictor app, here is the link-
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor.

No, your marks are less to get an NIT, but you can get other government college of your state. Stay aware about counseling. You can prefer Shiksha JEE Mains college predictor app to get more insight about college you can get.

NCERT books are best for JEE preparations.