Hello,
.
You cannot apply for a Government college in every State. There are only 2 possibilities. One is you should have domicile of the State and 2 is that you should participate in All India Counselling. In any way you try, 400 is a very less score. You did not mention your Category. Still 400 is going to be a very less score. Government Colleges do not have Management quota also. So if you want a seat in BDS and if you belong to General Category, your target should be 500 -550 and if you belong to OBC/SC/ST, your target should be 475-500.
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile