Answers for ".card-wrap bootstrap"

bootstrap card change image

.card-img-top {
    width: 100%;
    height: 15vw;
    object-fit: cover;
}

box around image and text using bootstrap 4

<div class="row">
  <div class="col-sm-6">
    <div class="card">
      <div class="card-body">
        <h5 class="card-title">Special title treatment</h5>
        <p class="card-text">With supporting text below as a natural lead-in to additional content.</p>
        <a href="#" class="btn btn-primary">Go somewhere</a>
      </div>
    </div>
  </div>
  <div class="col-sm-6">
    <div class="card">
      <div class="card-body">
        <h5 class="card-title">Special title treatment</h5>
        <p class="card-text">With supporting text below as a natural lead-in to additional content.</p>
        <a href="#" class="btn btn-primary">Go somewhere</a>
      </div>
    </div>
  </div>
</div>