In order to run the What-If Tool in a webpage like the demos do, you would need to build that webapp separately instead of trying to convert from the notebook.
Those demos use models that run in the browser directly using TensorFlow.js. If instead you want to build a webapp with the What-If Tool that queries a model running in python, you would need to write javascript code to query that model from your webserver (or something similar) and provide the results back to the tool, in the same manner as the
demo code does with the results from the TensorFlow.js models.