Hi Nayan,
The process of admission to colleges varies from course to course. For some courses, you may need to take an admission test. If you are shortlisted, you may then need to appear for a personal interview. Whereas, for other courses, just the score of your Class 12 Board Exam may be sufficient.
You need to first identify which course you want admission in. Second, dig out the last date of application and apply to that college. Third - wait for their first cut-off list. If you make it through, just go and submit the course fee and take admission.
Many universities are conducting the admission process for UG courses at present. We suggest that you start applying now or you could speak to our counselor to get guidance. The number is # 0141-3990699. Good luck!