But my aggregate marks in physics maths and computer science is more than 50%

Hello Aryan,In the greater part of Universities the base criteria for affirmation in Engineering is 50% aggregate in PCM in 12th class and not the % aggregate marks which do not contain PCM group.don't stress, so in this situation you have two options either go for subject improvement program or  there is another choice for you to do Diploma in Engineering (Polytechnic) in this you will be applying for 2nd year diploma then later on based on your third year diploma marks then you can apply for engineering 2nd year. Both are better options but I would prefer going for diploma 2nd year so if in third year you achieve great score then you can easily apply for Govt colleges, coz even with 108 score its difficult to get admission into Govt colleges.All the Best!!