Is there any reference how I’d get by creating an interactive demo in the browser using a Pytorch model?
Maybe something like this or this
You have to see the PyTorch model as a building block in the whole demo. There’s a backend and a frontend and many things happening in those demos, and this forum is not really dedicated to building websites 
But of course you can create a python backend (bottle, flask…) and any frontend you like, or use full-stack frameworks, and use PyTorch code inside when processing client requests. Or even another backend that can call python code 