Dear Ravi,
I think you have underestimating your ability at this juncture. Getting not healthy marks in your 12th class doesn’t means that all the doors are closed for you. You can still able to get admission in some regular courses. But I am afraid that some reputed college will not consider you in some streams like science etc., but don’t lose your hope as still some regular colleges will consider you against this result.
Alternatively you can seek admission in some private institutions or colleges. Here you can able to opt reputed course in computer science or engineering in order to brighten your future ahead.
All the best for brighter career ahead.