Hey dash! Thanks for your question, however, I'm not too sure what you mean by what my index.html looks like. Because this uses React as frontend, I just used npx create-react-app to create my react folders and files (index.html is automatically created and I didn't edit or do anything with it). In React, once you're done editing your frontend codes, you run npm run build to create a build folder that is now ready for deployment. Then you basically "point" your backend (app.py) to your build folder and also show index.html as the home page.

Here's the GitHub repository: https://github.com/Reine0017/reactFlaskTutorial