how to link a google style sheet html code example

Example 1: import google font css

@import url('https://fonts.googleapis.com/css?family=Open+Sans&display=swap');
.generic_class {
	font-family: 'Open Sans', sans-serif;
}

Example 2: embed google font css

<link rel="stylesheet" href="//fonts.googleapis.com/css?family=Open+Sans:300,400,600,700&lang=en" />