npx create-react-app

You are running `create-react-app` 4.0.0, which is behind the latest release (4.0.1).

We no longer support global installation of Create React App.

Please remove any global installs with one of the following commands:
- npm uninstall -g create-react-app
- yarn global remove create-react-app

The latest instructions for creating a new app can be found here:
https://create-react-app.dev/docs/getting-started/

이러한 에러가 발생한다면 ,

npm uninstall -g create-react-app
npm add create-react-app
다시 npx create-react-app [app-name]