How to claim maintenance from father for daily essential expenses?

Hello sir , well i want to consult u that nothing is working between my parents my father is harrasing my mother and giving her mental torcher , he doesn't give a single rupees to her to spent . She works for her own livelihood and also pay us . My father doesn't even give money for our pocket money also he refuse to bring grocery and other home things while living in a same house with my mother . He refuse to give single money and says that uts all what his father left for him . We all die day by day as expenses are alot but we dont have money to spent as our father doesn't support please suggest what we can do legally in this so that we get our case of money so that we can study further and also my mother can get her share for living ?