I want to accomplish 2 things in my woocommerce checkout form: 1. Put some text between some groups of fields, for example (h3):
my custom heading&
For the first one you can do the following to display single input field
checkout_fields['billing']['billing_first_name'],
$checkout->get_value( 'billing_first_name' )
);
?>
where you can replace first_name
with any key of the checkout billing fields
So for your example it will be something like this
my custom heading
checkout_fields['billing']['billing_email'], $checkout->get_value( 'billing_email' ) ); ?>
As for the second I'm not sure how you can achieve that. I needed something similar and i used javascript to reposition the labels.
something like :
jQuery('form.checkout label').each(function(){
jQuery(this).insertAfter(jQuery(this).parent().find('input'));
})