Bootstrap - Extend link to parent (stretched-link)

 <div class="card" style="width: 18rem;">

  <img src="..." class="card-img-top" alt="...">
  <div class="card-body">
    <h5 class="card-title">Card with stretched link</h5>
    <p class="card-text">Some quick example text to build on the card title and make up the bulk of the card's content.</p>
    <a href="#" class="btn btn-primary stretched-link">Go somewhere</a>
  </div>
</div>

https://getbootstrap.com/docs/4.3/utilities/stretched-link/