Answers for "bootstrap css col md 4 center"

bootstrap col center content

<div class="row">
    <div class="col-4 d-flex justify-content-center text-center">
        // for image and text
    </div>
</div>

bootstrap col-md-5 center

<div class="container">
  <div class="row">
     <div class="col-sm-5 mx-auto">
        Centered
    </div>
  </div>
</div>