<main>
  <section>
    <div class="testimonial">
      <div class="container">
       <div class="testimonial__inner">
         <div class="testimonial-slider">
           <div class="testimonial-slide">
             <div class="testimonial_box">
               <div class="testimonial_box-inner">
                 <div class="testimonial_box-top">
                   <div class="testimonial_box-icon">
                     <i class="fas fa-quote-right"></i>
                   </div>
                   <div class="testimonial_box-text">
                     <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Delectus optio facilis beatae.</p>
                   </div>
                  <div class="testimonial_box-name">
                    <h4>John Doe</h4>
                 </div>
                 <div class="testimonial_box-job">
                   <p>MANAGER</p>
                 </div>
                 </div>
               </div>
             </div>
           </div>
           <div class="testimonial-slide">
            <div class="testimonial_box">
              <div class="testimonial_box-inner">
                <div class="testimonial_box-top">
                  <div class="testimonial_box-icon">
                    <i class="fas fa-quote-right"></i>
                  </div>
                  <div class="testimonial_box-text">
                    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Delectus optio facilis beatae.</p>
                  </div>
                 <div class="testimonial_box-name">
                   <h4>Anna Mull</h4>
                </div>
                <div class="testimonial_box-job">
                  <p>CEO</p>
                </div>
                </div>
              </div>
            </div>
          </div>
          <div class="testimonial-slide">
            <div class="testimonial_box">
              <div class="testimonial_box-inner">
                <div class="testimonial_box-top">
                  <div class="testimonial_box-icon">
                    <i class="fas fa-quote-right"></i>
                  </div>
                  <div class="testimonial_box-text">
                    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Delectus optio facilis beatae.</p>
                  </div>
                 <div class="testimonial_box-name">
                   <h4>Gail Forcewind</h4>
                </div>
                <div class="testimonial_box-job">
                  <p>Co-Founder</p>
                </div>
                </div>
              </div>
            </div>
          </div>
          <div class="testimonial-slide">
            <div class="testimonial_box">
              <div class="testimonial_box-inner">
                <div class="testimonial_box-top">
                  <div class="testimonial_box-icon">
                    <i class="fas fa-quote-right"></i>
                  </div>
                  <div class="testimonial_box-text">
                    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Delectus optio facilis beatae.</p>
                  </div>
                 <div class="testimonial_box-name">
                   <h4>Johanna smith</h4>
                </div>
                <div class="testimonial_box-job">
                  <p>SEO</p>
                </div>
                </div>
              </div>
            </div>
          </div>
         </div>
       </div>
      </div>
    </div>
  </section>
</main>

*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
  }
  
.testimonial{
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #212529;
    color: #212529;

    &-slide{
        padding:40px 20px;
    }
    &_box{   

        &-top{
            background-color: #e9ecef;
            padding: 30px;
            border-radius: 15px;
            display: flex;
            justify-content: center;
            align-items: center;
            flex-direction: column;
            text-align: center;
            box-shadow: 2px 2px 10px rgba(206, 212, 218, 0.534);
        }
        &-icon{
            padding: 10px 0;
            i{
                font-size: 25px;
                color: #212529;
            }
        }
        &-text{
            padding: 10px 0;
            p{
                color: #212529;
                font-size: 14px;
                line-height: 20px;
                margin-bottom: 0;
            }
        }
        &-name{
            padding-top: 10px;
            h4{
                font-size: 20px;
                line-height: 25px;
                color: #212529;
                margin-bottom: 0;
            }
        }
        &-job{
            p{
                color: #212529;
                font-size: 14px;
                text-transform: uppercase;
                letter-spacing: 3px;
                line-height: 20px;
                font-weight: 300;
                margin-bottom: 0;
            }
        }
    }
}

.slick-dots {

    li{
        padding: 0 30px;
        opacity: 0.5;

        button{
            content:url(https://i.ibb.co/hKgs8gm/profile.jpg);
            background: url(https://i.ibb.co/hKgs8gm/profile.jpg);
            background-position: center !important;
            background-size: cover !important;
            text-indent: -9999px;
            overflow:hidden;
            width: 60px;
            height: 60px;
            border-radius: 50px;
            border: 4px solid #dee2e6;
        }
    }

    .slick-active{
        opacity: 1;
    }
}
View Compiled
$(document).ready(function() {
    $('.testimonial-slider').slick({
        autoplay: false,
        autoplaySpeed: 1000,
        speed: 600,
        draggable: true,
        infinite: true,
        slidesToShow: 1,
        slidesToScroll: 1,
        arrows: false,
        dots: true,
    });

    $('.slick-dots li:nth-child(1)').html('<button style="background: url(https://i.ibb.co/JQ18QKW/asd.jpg);"></button>');
    $('.slick-dots li:nth-child(2)').html('<button style="background: url(https://i.ibb.co/hKgs8gm/profile.jpg);"></button>');
    $('.slick-dots li:nth-child(3)').html('<button style="background: url(https://i.ibb.co/Q8zzbCR/profile1.jpg);"></button>');
    $('.slick-dots li:nth-child(4)').html('<button style="background: url(https://i.ibb.co/tPFqymw/profile2.jpg);"></button>');
}); 

External CSS

  1. https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css
  2. https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css
  3. https://cdnjs.cloudflare.com/ajax/libs/slick-carousel/1.8.1/slick-theme.css
  4. https://cdnjs.cloudflare.com/ajax/libs/slick-carousel/1.8.1/slick.css

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js
  2. https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.bundle.min.js
  3. https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js
  4. https://cdnjs.cloudflare.com/ajax/libs/slick-carousel/1.8.1/slick.js