Ownership Right to sell

Me & my husband has purchased flat jointly & I am a co-owner in home loan also. Emi was paid by husband till date & I am housewife. Society share certificate has name of both with oblique.( First is of my husband & second of mine). There is no Nominee in society records. Recently my husband died in an accident without any will.I have 2 children & both are minor.My mother in law & father in law are alive.Currently my In laws are occupied the flat.I would like to sell the flat and move to other city. I have below queries. 1) What is my share in flat along with my children. 2) Can I sell the flat without consent of my mother in law.As I am a co-owner of flat. 3) What is my loan liability. 4) How to take custody of flat.( In laws are opposing for any release deed & vacating the flat) 5)Mother in law has already approached court for Sucession. 6) How much it will take if I approach court for the same. 7)Is it possible if I sell it & make the payment of her share.Can she approach court for cancellation of sell deed or restraining order for sell. Suggest suitable lawyer in Nagpur to move forward.