npm install bootstrap --save
or
yarn add bootstrap
If you are using SCSS, don't add it to your angular.json config. Instead, add this to your <code>scr/styles.scss</code> directly:
<pre><code class="lang-scss">@import '../node_modules/bootstrap/scss/bootstrap';
</code></pre>
if you are using css
<pre><code class="lang-javascript">"styles": [
 "node_modules/bootstrap/dist/css/bootstrap.css",
 "src/styles.css"
 ],

 "scripts": [
 "node_modules/popper.js/dist/umd/popper.min.js",
 "node_modules/bootstrap/dist/js/bootstrap.min.js"
 ]
</code></pre>

npm install bootstrap --save

or

yarn add bootstrap

**If you are using SCSS**, don't add it to your angular.json config. Instead, add this to your `scr/styles.scss` directly:

```scss
@import '../node_modules/bootstrap/scss/bootstrap';
```

if you are using css

```javascript
"styles": [
          "node_modules/bootstrap/dist/css/bootstrap.css",
          "src/styles.css"
        ],

        "scripts": [
          "node_modules/popper.js/dist/umd/popper.min.js",
          "node_modules/bootstrap/dist/js/bootstrap.min.js"
        ]
```

Using Bootstrap in Angular with SCSS