JEE

may be in state gov collage.

Click the following link for detailed information :
http://www.chitkara.edu.in/admissions/admission-procedure/
The chances are very less based on your JEE score, but you can sneak in based on your percentage but the availability of required stream may vary

No,its not possible.

u can prefer any branch as it depends on your interest but as u score less you can prefer electronics or extc as it is avg and evergreen branch .If u have interest in computer then I prefer you go to computer engineering and not MSCIT

There are many good colleges in punjab where you can get admission.some of these premier institutes are
1.NIT jalandhar
2.Lovely Professional University
3.Thapar University
these all are doing exceptionally good these days.Lovely Professional University is having a tie-ups with more than 50 countries of the world providing an excellent platform to their students to boost their skills.They venture in their students an unmatched entrepreneurial skills that makes their students an efficient manager.

u can get depending upon the 12 board score as it has weightage of 40 percent and u can't get the top 5 nits and even your wished branch

Only only & only practice can help u a lot.
More & more problems will help in clear the concept & application of formulas.
You should focus on boosting your speed, revise end result, key points of some chapter.

Yes, this rank will probably get you admitted to the NCR campus.

For getting computer engineering you should score above 200 atleast in mains and above 95% in boards. The criteria will change next year as board marks will not be considered. For other branches try scoring above 170 in mains and 92% in boards. This will atleast get you into NSIT if you desperately want it.