installing react and express

Need to install the following packages:
  create-react-app
Ok to proceed? (y) y

You are running `create-react-app` 4.0.3, which is behind the latest release (5.0.0).

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/

バージョンがアップグレードされた場合、適切ではないかもしれませんが、削除して再インストールすればいいです.

npm uninstall -g create-react-app// 이것은 먹히지 않음 

npx clear-npx-cache // ok!!

npx create-react-app project-name

サーバの作成
reference: https://velog.io/@new_wisdom/Node.js-6-Express-Express-generator%EB%A1%9C-%ED%94%84%EB%A1%9C%EC%A0%9D%ED%8A%B8-%EB%A7%8C%EB%93%A4%EA%B8%B0

npx express-generator --no-view project-name

or

npx express-generator project-name

defference between npm and npx
reference: https://webruden.tistory.com/275