I like to use TypeScript instead of JavaScript. I use TS with: pure WebGL, Phaser (2D), Babylon.js (3D). I study network programming using Node.js and socket.io. Free hosting Heroku has these database: MySQL, MongoDB and Postgres. You can make auto deplay from GitHub when you make "git push"

I prefer C#/OpenTK/OpenGL3 because you can use C# with Unity. Unity is very popular game engine. There are a lot of jobs. C# is friendly and simpler than C++. I study how to write a simple game server using TCP sockets in C#. You can use OpenTK with WinForms and WPF. OpenTK has ability to create GameWindow.