https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Tutorial
index.html
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<canvas id="canvas"></canvas>
<script src="script.js"></script>
</body>
</html>
script.js
console.log("hello")
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
ctx.fillStyle = 'green';
ctx.fillRect(10, 10, 150, 100);
