Hello.

If a college is affiliated to some state gov Universities then you have to get atleast 50% of 12th score.

You have two options now as your percentile is low.

1. You can try to get in some average engineering colleges. But then you will have to compromise on your expectations of a good engineering college! If you can pay hefty donations you can get into any good decent college!
2. Here if you are not getting admit in any of the colleges after 12th. You can opt for Direct second year admission in diploma course. Generally it is a 3 year course but after 12th you get a lateral entry. After completion of diploma course you can opt of Direct second year Engineering (BE) or (Btech)through cap process or Management quota.

If you don't have the min 12th score then there is only one option (1).

Hope this is helpful.

Good luck.