<div id="carouselExampleIndicators" class="carousel slide mb-3" data-ride="carousel">
  <ol class="carousel-indicators">
    <li data-target="#carouselExampleIndicators" data-slide-to="0" class="active"></li>
    <li data-target="#carouselExampleIndicators" data-slide-to="1"></li>
    <li data-target="#carouselExampleIndicators" data-slide-to="2"></li>
  </ol>
  <div class="carousel-inner">
    <div class="carousel-item active">
      <a target="_blank" href="http://www.huux.cc"><img class="first-slide rounded" src="https://img.zcool.cn/community/0116ed5e1be011a80121651832a214.png@1380w" alt="First slide"></a>
    </div>
    <div class="carousel-item">
      <a target="_blank" href="http://www.huux.cc"><img class="first-slide rounded" src="https://img.zcool.cn/community/0181e35e1be025a80121651856a646.png@1380w" alt="Second slide"></a>
    </div>
    <div class="carousel-item">
      <a target="_blank" href="http://www.huux.cc"><img class="first-slide rounded" src="https://img.zcool.cn/community/012ca45e1be040a80121651804ca4e.png@1380w" alt="Third slide"></a>
    </div>
  </div>
  <a class="carousel-control-prev" href="#carouselExampleIndicators" role="button" data-slide="prev">
    <span class="carousel-control-prev-icon" aria-hidden="true"></span>
    <span class="sr-only">Previous</span>
  </a>
  <a class="carousel-control-next" href="#carouselExampleIndicators" role="button" data-slide="next">
    <span class="carousel-control-next-icon" aria-hidden="true"></span>
    <span class="sr-only">Next</span>
  </a>
</div>

添加代码到下图位置