Modify WooCommerce Checkout Fields Template

functions.php

<?php

add_filter( 'woocommerce_checkout_fields' , 'yanco_remove_woo_checkout_fields' );
function yanco_remove_woo_checkout_fields( $fields ) {
    // remove billing fields
    unset( $fields['billing']['billing_company'] );
    unset( $fields['billing']['billing_address_2'] );
    // remove order comment fields
    // unset($fields['order']['order_comments']);
    return $fields;
}
add_filter( 'woocommerce_checkout_fields' , 'yanco_override_checkout_fields' );
function yanco_override_checkout_fields( $fields ) {
    $fields['billing']['billing_postcode']['class'] = array('form-row', 'form-row-first') ;
    $fields['billing']['billing_city']['class'] = array('form-row', 'form-row-last') ;
    $fields['billing']['billing_email']['class'] = array('form-row', 'form-row-first') ;
    $fields['billing']['billing_phone']['class'] = array('form-row', 'form-row-last') ;
    $fields['billing']['billing_country']['class'] = array('form-row', 'form-row-first') ;
    // $fields['order']['order_comments']['class'] = array('form-row', 'notes', 'form-row-wide');
    $fields['order']['order_comments']['placeholder'] = 'Besked om denne bestilling (kan forsinke ekspeditionen)';
    $fields['order']['order_comments']['label'] = 'Ordre notat';
    return $fields;
}

/**
 * Remove Additional Information
 */
	add_filter( 'woocommerce_enable_order_notes_field', 'yanco_woocommerce_enable_order_notes_field' );
	function yanco_woocommerce_enable_order_notes_field() {
		return false;
	}

	add_action( 'woocommerce_checkout_fields', 'yanco_woocommerce_checkout_fields' );
	function yanco_woocommerce_checkout_fields( $fields ) {
		// Stop Scrolling to first empty field in checkout form
		$fields['billing']['billing_email']['autofocus'] = false;
		$fields['billing']['billing_first_name']['autofocus'] = false;
		unset( $fields['billing']['billing_address_2'] );
		$fields['billing']['billing_company']['priority'] = 4;
		$fields['billing']['billing_postcode']['class'][] = 'form-row-first';
		$fields['billing']['billing_city']['class'][] = 'form-row-last';
		$fields['billing']['billing_phone']['priority'] = 21;
		unset( $fields['billing']['billing_phone']['class'] );
		$fields['billing']['billing_phone']['class'][] = 'form-row-wide';
		foreach( $fields['billing']['billing_postcode']['class'] as $key => $class ) {
			if( $class === 'form-row-wide' ) {
				unset( $fields['billing']['billing_postcode']['class'][$key] );
			}
		}
		foreach( $fields['billing']['billing_city']['class'] as $key => $class ) {
			if( $class === 'form-row-wide' ) {
				unset( $fields['billing']['billing_city']['class'][$key] );
			}
		}
		return $fields;
	}