ishanr

$my_query_args = array(
            'family' => 'Montserrat:400,700:latin'
        );
    wp_enqueue_style('custom-google-fonts', add_query_arg( $my_query_args, "$protocol://fonts.googleapis.com/css" ), array(), null );

I like Open Sans, so I didn’t touch that or dequeue it. Just added another enqueue style for the Montserrat Font.