How to Start a Career in Blockchain Security [on hold]

I’m a Software Engineering Fresh Graduate, My Only knowledge is in Application Development. I wanted to start a career in Blockchain Security but i don’t know where to start from. I’m basically doing a career shift and i don’t have any background. can Someone explain to me how to start? What are the courses and certificates that i need? how long will it take me? and what is the best path i can follow to reach that goal? Thanks For Your Time.

Lastly, if I’m asking in the wrong site can someone tell me where i can submit my question?