Show percentage in Pie Piece

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.2/Chart.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/chartjs-plugin-datalabels.min.js"></script>
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">

<!-- jQuery library -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>

<!-- Popper JS -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"></script>

<!-- Latest compiled JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>   
   
   <section id="main-content">
                <div class="container">
                        <div class="row" id="top-content">
                            <div class="col-lg-4" id="left-content">
            
                                <h1 class="flex-item1">1</h1>
                                <div class="card-custom flex-item2">
                                2
                                </div>
            
                            </div>
                            <div class="col-lg-8" id="right-content">
                                    <div class="flex-item3"> 3
                                    </div>
                            </div>
                        </div>
                </div>
                        
        </section>

CSS

.flex-item1 {
        background:skyblue;
        width; 150px;
        height: 100px;
       }
   .flex-item2{
      width: 150px;
      height: 100px;
      background: green
   }
   .flex-item3{ 
      width: 300px;
      height: 400px;
      background: red;
   }
   
   @media only screen and (max-width: 600px) {
    .flex-item1 {
        order: 1; 
       }
   .flex-item2{
        order: 3;
   }
   .flex-item3{ 
       order: 2; 
   }
}