<canvas id="my-canvas" width="650px" height="500px">
</canvas>

let myCanvas = document.getElementById('my-canvas');

let ctx = myCanvas.getContext('2d');

ctx.strokeStyle ='green';
ctx.lineWidth = 20;
ctx.lineJoin = 'round';

ctx.beginPath();
ctx.moveTo(75, 75);
ctx.lineTo(200, 150);
ctx.lineTo(325, 75);
ctx.lineTo(450, 150);
ctx.lineTo(575, 75);
ctx.stroke();
ctx.stroke();