The School of Investment Banking

To get a job as an investment banker, you need the certificate in this field. You have to obtain that certificate with significant amount of work experience in accounting/finance field. Since you are doing MBA Finance, it will also makes a positive impact on your profile. To be the portfolio manager, you must have to be enough qualified. Apart from your academics, if you have well on job experience in this particular field, you can straightly join as the senior post.
My opinion is that along with (or after with) the certification of investment banking, if possible try to get the certification of CFA. It will surely help you to understand the core mechanisms of your job.