Check out example codes for "adding css to html". It will help you in understanding the concepts better.
Code Example 1
<!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 2
<head>
<link rel="stylesheet" type="text/css" href="theme.css">
</head>
Code Example 3
<link rel="stylesheet" href="styles.css">
Code Example 4
<head>
<!-- Linking external Css document -->
<link rel="stylesheet" href="styles.css">
<!-- Writing Css inside HTML element -->
<style>
...
</style>
</head>
Code Example 5
<link rel="stylesheet" type="text/css" href="style.css">
Code Example 6
/*
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
*/
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