<canvas id="canvas"></canvas>
const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
ctx.fillStyle = "green";
ctx.fillRect(10, 10, 150, 100);
<canvas id="canvas"></canvas>
const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
ctx.fillStyle = "green";
ctx.fillRect(10, 10, 150, 100);