Edit in JSFiddle

<!DOCTYPE HTML>
<html>
    <head>
        <style>
            body {
                margin: 0px;
                padding: 0px;
            }
            
            #myCanvas {
                border: 1px solid #9C9898;
            }
            
            #yLeg {
                position:absolute;
                top:50px;
                left:30px;
                width:120px;
                text-align:right;
                font:15px arial,sans-serif;
            }
            #xLeg {
                position:absolute;
                top:170px;
                left:290px;
                width:120px;
                text-align:right;
                font:15px arial,sans-serif;
            }
        </style>
        <script>
            
                window.onload = function(){
                var canvas = document.getElementById("myCanvas");
                var context = canvas.getContext("2d");
                
                context.moveTo(160, 100);
                
                var controlX1 = 350;
                var controlY1 = 70;
                var controlX2 = 460;
                var controlY2 = -50;
                var endX = 488;
                var endY = 170;
                
                context.bezierCurveTo(controlX1, controlY1, controlX2, controlY2, endX, endY);
                
                context.lineWidth = 4;
                context.strokeStyle = "black"; // line color
                context.stroke();
            
                context.moveTo(155, 160);
                context.lineTo(550, 160);
                context.lineWidth = 0.2;
                context.stroke();
                
                context.moveTo(160, 170);
                context.lineTo(160, 10);
                context.lineWidth = 0.2;
                context.stroke();
            };
        </script>
    </head>
    <body onmousedown="return false;">
        <canvas id="myCanvas" width="578" height="200">
        </canvas>
        <div id="yLeg">
            Social, economic and environmental relevance of the topics in discussion.
        </div>
        <div id="xLeg">
            Alcohol intake.
        </div>
    </body>
</html>