Basically, all programmers use a java script to develop their applications. It is a programming language and is easy to learn and use. But to create a backend, Node.js comes to the rescue. This article explains it all very well - the reasons for using it, all the functionality. Maybe someone else will suggest something else, but I advise you to read all the questions here go now
Everything needs to be studied, thank you. Which is what I've been doing for a year now. And still not much time yet.