To start a career as a financial advisor which are the series exams you need to pass?

Answer 1

Series 6 and 63

The series 6 allows you to sell mutual funds, etc, but if you want to sell stocks, you'd need Series 7 and Series 63 instead.

To take the exams, you need to be sponsored by a Financial Services firm.

So it usually works something like this:

Apply for a job with a firm - Receive a tentative offer - Study and complete your Series 6/7 and 63. Then, receive an official job offer, and get to work :)