webpack.config.js

const path = require("path");
const HtmlWebpackPlugin = require("html-webpack-plugin");

module.exports = {
  module: {
    rules: [
      {
        test: /\.css$/i,
        use: ["style-loader", "css-loader"],
      },
    ],
  },
};

 module.exports = {
   entry: "./src/App.jsx",
   output: {
     filename: "main.js",
     path: path.resolve(__dirname, "build"),
   },
   plugins: [
     new HtmlWebpackPlugin({
       template: path.join(__dirname, "public", "index.html"),
     }),
   ],
   devServer: {
     static: {
       directory: path.join(__dirname, "build"),
     },
     port: 3000,
   },
   module: {
     // exclude node_modules
     rules: [
       {
         test: /\.(js|jsx)$/,
         exclude: /node_modules/,
         loader: "babel-loader",
         options: { presets: ['@babel/env','@babel/preset-react'] }
       },
       {
        test: /\.css$/i,
        use: ["style-loader", "css-loader"],
      },
     ],
   },
   // pass all js files through Babel
   resolve: {
     extensions: ["*", ".js", ".jsx"],
   }
 };