Check out example codes for "add css file in html". It will help you in understanding the concepts better.

Code Example 1

<link rel="stylesheet" href="PathToYourFile.css">

Code Example 2

<head>

       
      <link rel="stylesheet" type="text/css" href="theme.css">

    </head>

Code Example 3

/*
Adding css file into html document
*/

<link rel="stylesheet" type="text/css" href="yourstylesheetname.css">  /* add this line into head tag of the file with change in file name. */

/*
I hope it will help you.
Namaste
*/

Code Example 4

<!DOCTYPE html>
<html>
<head>

  <link rel="stylesheet" href="styles.css">

</head>
<body>

<h1>This is a heading</h1>
<p>This is a paragraph.</p>

</body>
</html>

Code Example 5

<link rel="stylesheet" type="text/css" href="stylesheet.css" media="screen"/>

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