As you have studied PCMB in intermediate, you can definitely go for B.Tech in computer science engineering. For that you need to appear for entrance exams as admission to most of the engineering colleges are done through entrance examination. Only a few colleges consider 12th score and offer admission on the basis of that. JEE Main is one of the most important national level exams for engineering aspirants. There is no percentage barrier to be eligible for Jee Main. The basic eligibility critdtia is that the candidate must have passed 10+2 with Physics, Mathematics as compulsory subjects [along with one of Chemistry/Biotechnology/Biology/Technical/Vocational] from a recognized board. You can also appear for state level entrance exams. It you are going to write neet, then you can get admission in medical, dental or ayush courses. But if you are interested in Engineering, mostly in CS, then you must go for it.