In answering the question, I too was vague. Point taken. I was referring to the nginx question specifically. And I
tried maybe not hard enough to convey that there is a need to start chasing down one question at a time. Don't most journeys start that way?
Also, my suggestion to learn more about servers in general, which I didn't actually answer, is to build one. If the OP wants a link to how to build a LAMP stack, I can supply an article series I wrote on the subject some time back. It's a little out of date, but the concepts apply.