How do you use the <canvas></canvas> tags?

Answer 1

simply place it on your html and get it's reference with javascript and control it from there

HTML
<canvas id="myCanvas"></canvas>

JavaScript
// get the <canvas> element from HTML
canvas=document.getElementById("myCanvas");
// get 2D context object
ctx=canvas.getContext("2d");
from here on you draw on the canvas with the ctx object

for example draw a red circle in coordinates (50,50) with radius of 10

ctx.fillStyle="red";
ctx.beginPath();
ctx.arc(50,50,10,0,Math.PI*2);
ctx.closePath();
ctx.fill();

here are some guide for some canvas methods

http://www.html5canvastutorials.com
https://www.w3schools.com/html/html5_canvas.asp
https://www.sitepoint.com/html5-canvas-tutorial-introduction/
http://codetheory.in/20-best-canvas-tutorials-and-examples-that-will-make-you-a-canvas-master/

API
https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API/Tutorial

Answer 2

The HTML <canvas> element is used to draw graphics, on the fly, via JavaScript.

The <canvas> element is only a container for graphics. You must use JavaScript to actually draw the graphics.

Canvas has several methods for drawing paths, boxes, circles, text, and adding images.

resources: https://www.w3schools.com/html/html5_canvas.asp