Advice Please: What programming languages do I need to learn in order to become a good Blockchain Developer?

Hi everyone,

I am looking for an advice. I am a developer who is mostly working with PHP & Javascript. What should my next step be in order to become a Blockchain Developer? What are the languages you would recommend? I really want to know what you thnik. I did some research and I really apreciate all the information out there but I am getting really confused in the same time.

Thank you in advance! :)