MANIT - Maulana Azad National Institute of Technology

Both are much respected institutes. Joining either of them would not be regretted.
You should consider other factors such as the location of your home town, branch you are getting, placement statistics, importance of NIT tag to you and then decide.
I can tell you 1 thing for sure, i.e. joining NIT-B would be one of the best things ever happened to you.

Go for MANIT CSE or B.Tech CSE programme instead of any dual degree at other institutions.

Sorry, you would not be able to get MANIT. Refer college predictors for more.

It depends on your category. If you are from general category, better not hope for the seat. If you belong to SC/ST category, you may get a seat.

No, you can't as the eligibility criteria is 75% boards and should have cleared the JEE mains.

You have to obtain 170+ marks as you are in General category. But there might be changes as every year cut off changes and even some of good students cannot get good colleges and desired branch because of their higher cut-offs. So, I will only tell you to try to get at least 200 marks so that you will able to get good branch in MANIT, Bhopal. Thanks.

MANIT, Bhopal is an autonomous university under the concern of government. It is not affiliated to any of the university.

Well, in accordance to the previous year's stat, for Home State (HS) quota-closing rank of different branches (7th round) are as follows:
CSE-2010, ECE-3554, EE- 3470, ME- 3086, civil- 1414, chem- 5041, and MSME- 7136.
For Other State Quota (OS):
CSE-1297, ECE-1730, EE-1216, ME-1480, Civil-871, Chem-2046, and MSME-3545.

Check out the college website and admission procedure or contact the number mentioned on it.

Cutoff varies per annum, basically selection is based on merit list. Check out website for more details. For admission on u need to personally verify the document at campus.