1 - There is a thing called WebGL(R) which is basically OpenGL(R) ES for JavaScript that draws to an HTML5 canvas.
2 - There is no such thing as an OpenGL(R) model format. You need to somehow load and interpret a model file with a format of your choice and generate a vertex buffer [and index buffer] from the data.
To clear a few missconceptions: OpenGL(R) is an API for hardware accelerated rasterization, not a fully featured 3D graphics rendering engine. The only thing OpenGL(R) handles is rasterizing triangles. It does not handle things like loading model data from some source or user input, etc…
If you want a simple, fully featured rendering engine that you can embedd into a website, you might be interested in something like Coppercube.