As you probably know it's always a good idea to register and enqueue your styles within you functions.php
.
As you can see in the Codex, there is a given order for the parameters of those functions. Simply put the data of the webfont in:
wp_register_style( $handle, $src, $deps, $ver, $media );
wp_enqueue_style( $handle, $src, $deps, $ver, $media );
So you'll probably have something like this in your functions.php
:
function load_google_webfonts() {
wp_register_style( 'bree', 'https://fonts.googleapis.com/css?family=Bree+Serif' );
wp_enqueue_style('style', get_stylesheet_uri(), array('bree'), '1.0', 'all');
}
add_action( 'wp_enqueue_scripts', 'load_google_webfonts' );