Greetings from ShepHertz!!!!
You will require separate Web GL SDK to build Web GL application with Unity platform. You can build Android, iOS platform apps using existing AppWarp S2 Unity SDK.
You can download Sample WebGL application, it contains AppWarp S2 WebGL SDK and WebSocket.jslib file, both are mandatory for Web GL unity application.
You can use Xampp/htdoc to host your generated WebGl application on local machine.
Let me know in case of more queries are there.