Github Pages with sveltekit only shows the HTML contents of app.html

I have a SvelteKit website deployed with Github Pages. All it shows is this:

The path is https://username.github.io/src/index.html. (I renamed app.html to index.html because routing to https://username.github.io/src/app.html didn't work for some reason).Why is it not working? Is it because I renamed app.html to index.html? If that's the case then what should I do?