<ul class="nav nav-tabs">
  <li class="nav-item me-1"><a href="#home" class="nav-link active" data-bs-toggle="tab">Home</a></li>
  <li class="nav-item me-1"><a href="#profile" class="nav-link" data-bs-toggle="tab">Profile</a></li>
  <li class="nav-item me-1 dropdown">
    <a href="#" class="nav-link dropdown-toggle" data-bs-toggle="dropdown">
      Dropdown
    </a>
    <div class="dropdown-menu">
      <a href="#dropdown1" class="dropdown-item" data-bs-toggle="tab">@fat</a>
      <a href="#dropdown2" class="dropdown-item" data-bs-toggle="tab">@mdo</a>
    </div> 
  </li>
</ul>
<div class="tab-content pt-3">
  <div class="tab-pane fade show active" id="home">...</div>
  <div class="tab-pane fade" id="profile">...</div>
  <div class="tab-pane fade" id="dropdown1">...</div>
  <div class="tab-pane fade" id="dropdown2">...</div>
</div>