Ask HN: Moving to the next level

So, imagine this https://github.com/enrmarc/minesweeper-api is a "real" product/service. Call it THE_APP. Just for the sake of this post, imagine that THE_APP does "something valuable" and people would love to pay for it (ignore that it's just a pseudo minesweeper api).

I know how to write code. I don't write excellent code. I'm getting paid for writing decent code. I'm not very experienced programmer. I know things like OOP, FP, MVC, patterns, Ruby, type systems, http, Java, Android, Scheme, databases, JS frameworks, eval/apply, PHP, etc.

Now, I have no idea about: scalable architectures, how to deal with hundred of thousands of users, db replication, real time, https/ssl, cloud, message systems like zmq, security... in summary I have no idea how to make THE_APP a service that could work in a happy real situation (millions of users, a lot of data, etc).

So my question is: how I can learn all of those things?