Can anyone explain kindly Canvas elements and their attributes ?

Question

Elements and attributes of canvas

Answer 1

A canvas has no valid child DOMElements if that's part of your question. Some people add a text node like <canvas>canvas not supported.</canvas> but you're not supposed to add span, p tags... in it.

The canvas has a height and width attribute which specify number of pixels width and height to use for its bitmap image. This doesn't need to match pixels displayed but often does.
More official documentation on these attributes are at:
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/canvas

If you're just starting to use the HTML5 canvas, you'll want to learn about its 2d context. Many properties and methods of the object returned from calling getContext('2d') on your canvas are explained here:
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D

That website explains in great detail many classes used with a canvas.

If that's too much detail for you and you want more of a beginner tutorial, check: https://www.w3schools.com/html/html5_canvas.asp