1, HTML
2, CSS

2.19, Linking CSS files

For the future, when you do projects, your CSS must not be in your HTML file because it would look kinda chunky so first we will create a CSS file and then link it to our HTML. Follow the steps.
1, First create your HTML file. (Go to your IDE, create a new file and save it as an HTML file)
2, Then create your CSS file. (Go to your IDE, create a new file and save it as a CSS file)
3, Make sure they are in the same folder (the same path).
4, Go to your HTML and write your basic code.
<html>
    <head>
        <title>How to link CSS</title>
    </head>
    <body>
    </body>
</html>
5, Then to link your CSS file, add a link tag to your HTML in your head tag. And then write the attribute href. Then write the name of your CSS file. Like this
<html>
    <head>
        <title>How to link CSS</title>
        <link href="style.css">
    </head>
    <body>
     </body>
</html>
6, Then at the last we will tell that our file is a CSS file by adding the attribute rel like this
<link href="style.css" rel="stylesheet" >
You have successfully linked your CSS file to your HTML file. So, if you write anything on the CSS file, it would add properties to your elements because it's linked to your HTML.
Try it yourself.