Check out example codes for "html basic structure". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
<html>
  
  <head>
  	<title>Some Title</title>
    <link href="css_file.css" rel="stylesheet"> <!-- external CSS -->
  </head>
  
  <body>
    <!-- main content -->
  </body>
  
</html>

Code Example 2

<!DOCTYPE html>
<head>
	<!-- Miscellaneous Stuff Here -->
</head>
<body>
	<!-- Main Divs here -->
</body>

Code Example 3

<!DOCTYPE html>
'Inserts the DTDs'

Code Example 4

<!DOCTYPE html>
<html>
<head>
	<title>PUT A TITLE HERE</title>
</head>
<body>
	<canvas id="canvas" width="200" height = "200"></canvas>

	<script type="text/javascript">
		//put your code here
	</script>
</body>
</html>

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