Customise Child Theme

I’m very inexperienced with www.remarpro.com and all that entails so bear with me – I’m trying to achieve what (at least what I think) should be very simple things:
1) Increase the size of the logo header image (HERE NOW: WHERE NEXT)
2) Change the font and font size of the Tagline (“If time does not stand still, why should we?)
3) Add widgets, which the theme does not allow in its original state.

After a LOT of playing around with Additional CSS within the Hitchcock theme using hundreds of different codes found on various forums, I have still achieved nothing. I have even tried several Google fonts plugins to change the font of the tagline – I managed to change the fonts of EVERY other text on the site except the one I really want to change.

So more drastic measures are required, I realise. I have now created a child theme so I can edit the code directly but any changes I make to the Style.css stylesheet aren’t showing up when I save them. I have Enqueued the stylesheets with code I got from another thread to resolve the issue of the social icons from the parent theme not showing up in the child theme. This is what I have in the functions.php file currently:

function hitchcock_child_enqueue_child_styles() {
$parent_style = 'parent-style'; 
	wp_enqueue_style($parent_style, get_template_directory_uri() . '/style.css' );
	wp_enqueue_style( 
		'child-style', 
		get_stylesheet_directory_uri() . '/style.css',
		array( $parent_style ),
		wp_get_theme()->get('Version') );
	}
add_action( 'wp_enqueue_scripts', 'enqueue_child_theme_styles', PHP_INT_MAX);
function enqueue_child_theme_styles() {
  wp_enqueue_style( 'parent-style', get_template_directory_uri().'/style.css' );
  wp_enqueue_style( 'hitchcock_fontawesome', get_template_directory_uri() . '/fa/css/font-awesome.css' );
}

Is there something wrong with this code that might be stopping the child theme changes from showing up? Or am I being a complete idiot and missing something simple? Please help!

The page I need help with: [log in to see the link]