Dear Student
Sorry to say but 50.8% is not quite a good score. Being from PCM stream you are eligible to do courses like B.tech with any specialization, B.A in Maths, Physics, Chemistry or any other subject , Bsc also in any of these speciality. You can also go for pursuing courses like B.com and BBA taken upon your interest. There's large scope of subjects to choose from but it'll be hard for you to find a college as the minimum eligibility criteria of most of the colleges range between 50 - 60% and you just surpass the criteria for some also it'll be almost impossible for you to get admissions in colleges having admissions on the basis of your 12th percentage. Best of luck, Hope this answer might help you.