The law is clear in express terms that a child after attaining the majority cannot claim maintenance from parents. But I am quite confident that court (Specially High court ) will come to your rescue and give a direction to your father to provide your educational and other expenses (if he is in a position to afford that) till you acquire your professional qualification. As you said that your father is an High Court advocate, the courts know how to extract the result by using its good offices. The two grounds that require to be put in your petition are that acceptance of Rs.8.00 lakh lumpsum compensation was a miscalculation from your mother side to give MCD. She calculated your daily expenses and the expenses to be incurred to obtain basic academic degree till you attain 18. Further, she being housewife calculated her daily expenses till her last day. With her medieval mindset she missed the ever changing world and a girl's requirements in 21t century. In this competitive world, mere basic degree will not put you to get decent job. So, professional qualification is required to go on in this world and it is the responsibility of the father and mother. As you did not have any saying when this absurd Rs.8.00 lakhs maintenance was reached for you and your mother, now you ask for revision of that amount. You will certainly succeed in your efforts and the High Court will help you.
But you have to reach the High court through lower courts. so engage a good advocate to challenge the Rs.8.00 lakh compensation in lower court.