bootstrap 4 thumbnail image code example
Example 1: how to make image responsive bootstrap 4
<img src="..." class="img-fluid" alt="Responsive image">
Example 2: image responsive bootstrap 4
<img class="img-fluid" src="" alt=""> //This will make your image responsive
Example 3: How to insert an image in bootstrap 4
<img src="path to image" class="description" alt="Rounded Image">