Buddy

1) In your child theme's functions.php file add:

function ghostpool_google_webfonts() {
    echo '';
}
add_action( 'wp_head', 'ghostpool_google_webfonts' );

Make sure you activate the child theme to load this code.

2) Go to Google Web Fonts website, select the font you want to use and copy the "Standard" code provided e.g.

<link href="https://fonts.googleapis.com/css?family=Roboto&display=swap" rel="stylesheet">

3) Add this to your code above e.g.

function ghostpool_google_webfonts() {
    echo '<link href="https://fonts.googleapis.com/css?family=Roboto&display=swap" rel="stylesheet">';
}
add_action( 'wp_head', 'ghostpool_google_webfonts' );

4) Now go to Appearance > Theme Options > Styling and add the name of the font in one of the Font text fields.