require bootstrap code example
Example 1: bootstrap link
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
Example 2: ./node_modules/bootstrap/dist/js/bootstrap.bundle.js
npm i --save-dev bootstrap@next bootstrap-loader tether jquery
Example 3: ./node_modules/bootstrap/dist/js/bootstrap.bundle.js
npm install --save resolve-url-loader --dev