title: Why do I get a Can not find module error when I run npx run dev?
body: <p>Why do I get a Can not find module error when I run npx run dev?</p>
  
  <p>before run 'npx run dev'</p>
  
  <p>I processed this</p>
  
  <p>Run the npm init command
  Webpack webpack-cli installation
  Configuring webpack.conifig.js
  Setting package.json
  node upgrade
  Creating client.jsx
  WordRelay.jsx component file creation etc.</p>
  
  <p>webpack.conifig.js</p>
  
  <pre><code>const path = require('path');
  
  module.exports = {
      name:'wordrelay-setting',
      mode:'development',
      devtool:'eval',
      resolve:{
          extensions:['.js','.jsx']
      },
  
      entry:{
          app:['./client']
      }, // 입력
  
      output: {
          path:path.join(__dirname,'dist'),
          filename:'app.js'
      },  // 출력
  
  };
  </code></pre>
  
  <p>package.json</p>
  
  <pre><code>{
    "name": "lecture",
    "version": "1.0.0",
    "description": "",
    "main": "index.js",
    "scripts": {
      "dev": "webpack"
    },
    "author": "hyun",
    "license": "ISC",
    "dependencies": {
      "react": "^16.8.6",
      "react-dom": "^16.8.6"
    },
    "devDependencies": {
      "webpack": "^4.37.0",
      "webpack-cli": "^3.3.6"
    }
  }
  </code></pre>
  
  <p>and github: 
  <a href="https://github.com/hyunsokstar/react_game_prac2" rel="nofollow noreferrer">https://github.com/hyunsokstar/react_game_prac2</a></p>