Checkout page and order of sections

You will need to make a child theme and copy some or all of the templates at
wp-content/plugins/woocommerce/templates/checkout/…
to
wp-content/themes/my-theme-child/woocommerce/checkout/…

If your theme has modified these templates, its the theme ones you need to copy to your child theme.

Edit the copy templates to suit. PHP skills or a developer will be needed. There will be an ongoing maintenance burden in keeping your modified templates in sync with developments in WP, WC and maybe your theme.

I copied templates to child directory and all. I managed to change lots of stuff, but simply cant find how to change those from my quesiton.

For example i want to make labels and forms inline.

This would require custom CSS; Wouldn’t be template related.

Second quesiton is how to change position Your order cart details (table with product items), and payment method

You’d need to change the order in which the hooks are loaded / fired. You should be able to do that by changing the templates as mentioned above, or you could change the loading priority of the hooks.

I totaly managed to fix hooks and filters. For example

$fields['shipping']['shipping_address_2'] = array(		'label'     => __('Address 2', 'woocommerce'),	    'required'  => true,	    'label_class'     => array('col-md-6 col-sm-6') ,  'input_class'     => array('col-md-6 col-sm-6')

Working like a charm. Just i have problem with countries dropdown.

$fields['billing']['billing_country'] = array(	

'type'              => 'select',
        'label'             => 'Country',
        'placeholder'       => '',
        'maxlength'         => false,
        'required'          => false,
        'class'             => array(),
        'label_class'       => array('col-md-6'),
        'input_class'       => array('col-md-6'),
        'return'            => false,
        'options'           => array( 'option_1' => 'Option 1 text',
  'option_2' => 'Option 2 text'),
        'custom_attributes' => array(),
        'validate'          => array(),
        'default'           => '',

			);

Dont know how to load options from woocomerce (All Countries) to select/dropdown ??