I am B.Com (1st-sem) student & have passed only 1 subject and got failed in the rest (5), what should I do to prepare for bank jobs?

Just focus on your studies, clear the exams in which you failed. All the banking jobs need an all clear result in graduation. You can perform well during your graduation as well as in bank entrance exams. Keep a focused approach towards your studies. There are many course material available for bank