<div class="dropdown">
  <button class="btn btn-primary dropdown-toggle" type="button" id="dropdownMenuButton" data-bs-toggle="dropdown" aria-expanded="false">
    Liste déroulante
  </button>
  <ul class="dropdown-menu" aria-labelledby="dropdownMenuButton">
    <li><a class="dropdown-item" href="#">Action</a></li>
    <li><a class="dropdown-item" href="#">Autre action</a></li>
    <li><a class="dropdown-item" href="#">Quelque chose d'autre</a></li>
  </ul>
</div>