How to deploy create-react-app with typescript to Netlify when page returns 404

Question

My Netlify hosted app keeps returning a 404 "Page Not Found". I've ran things as simply as I can:

• I've followed the instructions on https://create-react-app.dev/docs/getting-started/ and am successfully running the react app on localhost.
• I've created an app on netlify and successfully connected to my
  github repository.
• When I click "Trigger Deploy" on Netlify, everything runs
  successfully.
• When I try to open the hosted app I get a 404 "Page Not Found"
  https://simple-cors-react.netlify.app/

Answer 1

Finally got it working by changing my deploy settings. I changed:

Build command: CI= yarn run build

Publish directory: ./build

(I get this error in the deploy log: 10:30:26 AM: Different publish path detected, going to use the one specified in the Netlify configuration file: 'build' versus './build' in the Netlify UI

Which begs the question "why didn't you just work before if it was already in the netlify configuration file?")