Check out example codes for "how to link external css to html". It will help you in understanding the concepts better.
Code Example 1
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="mystyle.css">
</head>
<body>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
</body>
</html>
Code Example 2
<link rel="stylesheet" type="text/css" href="mystyle.css">
Code Example 3
<link rel=“stylesheet” type=“text/css” href=“style.css” />
Code Example 4
<link rel="stylesheet" type="text/css" href="style.css">
Code Example 5
<link rel="stylesheet" href="PathToYourFile.css">
Code Example 6
<head>
<link rel='stylesheet' href='style.css'>
</head>
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