What's the best apporach to devolp the skills needed to transfer from BA to Data Science?

I gradudate from universtiy with a bachlor and master degree in semiconductor, but just to found myself interest in data analysis during daily work after graduate. I have worked as an analyst for semiconductor manufacturing company for several years, and then luckily to get a chance to work for Amazon, to support data analysis work of call center. With many years of work experience, I always have the feeling that I am not competent enough as a real data analyst. How should I build my technical skills systematically, to become a real data scientist in future?