With the presence of like-minded people, Delhi University offers the best exposure on campus. You will be interacting with experts from various fields and you should make the most of it. 

It is important to keep yourself updated with current affairs. Do not bulk things up and start studying on a daily basis. You can focus fully on UPSC preparation as DU gives less attention to attendance.

The syllabus for UPSC requires a basic knowledge of topics from History, Economics, Political Science, Environmental Science. For this, the best suitable program will be BA Programme to study at DU.

If you have enrolled in any other subject, then you should start studying topics from NCERT and current affairs. Apart from this, joining a coaching institute will always be an option but self-study is more important.