You built through the app door. Now build through the classic one and feel that it is the same engine. The workflow is identical: describe, watch, approve, open, refine. Claude Code asks permission before creating or changing files, so you stay in the loop.
In your empty my-first-app folder, with claude running, paste this (edit the topic to something you care about):
Approve its steps. When it finishes, find index.html in the folder and double-click it. That page in your browser? You made that.
The build fails, or the page opens blank? Paste the error, or a screenshot of what you see, back into Claude Code and say "fix this". That is not a failure of the workflow, that IS the workflow. Nobody's first build is clean, including the people who built this course.
Done when: your page opens in a browser and you have asked for at least two changes ("make the header green", "add a sort button") and watched them appear.