Dynamic Remarketing For Wordpress (New GTag)

function.php

function cp_dynamic_remarketing_tag()
{
		global $woocommerce; 
		$adword_code = 'AW-00000001';
		if(is_front_page() || is_home()){
		?>
		<script type="text/javascript">
			 gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_pagetype': 'home'
			  });
		
		</script>
		<?php
		}
		// Check if it is a product category page and set the category parameters.
		elseif (is_product_category()){
			
		?>
		<script type="text/javascript">
			
			 gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_pagetype': 'category',
				'ecomm_category': '<?php echo single_term_title();?>'
			 });
		</script>
		<?php
		}
		// Check if it a search results page and set the searchresults parameters.
		elseif (is_search()){
		?>
		<script type="text/javascript">
			gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_pagetype': 'searchresults'
			});
		</script>
		<?php
		}
		// Check if it is a product page and set the product parameters.
		elseif (is_product()){
		?>
		<script type="text/javascript">
			gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_pagetype': 'product',
				'ecomm_prodid': '<?php echo get_the_ID(); ?>',
				'ecomm_totalvalue': <?php 				
			$product = get_product( get_the_ID() );
			echo str_replace(",","",$product->get_price());						
			?>,
				'ecomm_category': '<?php echo single_term_title();?>'
			 });
		</script>
		<?php
		}
		// Check if it is the cart page and set the cart parameters.
		elseif (is_cart()){
		?>
		<script type="text/javascript">
		gtag('event', 'page_view', {
			'send_to': '<?php echo $adword_code;?>',
			'ecomm_prodid': <?php 
				echo "[";
					
				$cartprods = $woocommerce->cart->get_cart();
				$cartprods_items = array();
			
				foreach((array)$cartprods as $entry){
					array_push($cartprods_items, "'" . $entry['product_id'] . "'");
				}
				echo implode(', ', $cartprods_items);
				
				echo "]";
				?>,
			'ecomm_pagetype': 'cart',
			'ecomm_totalvalue': <?php echo str_replace(",","",number_format($woocommerce->cart->total,2)); ?>
		
		});
		</script>
		<?php
		}
		// Check if it the order received page and set the according parameters
		elseif (is_order_received_page()){
		?>

		<script type="text/javascript">
			gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_prodid': <?php
			
					echo "[";
					
					$order       = new WC_Order(wc_get_order_id_by_order_key($_GET['key']));
					$order_total = $order->get_total();
					$items = $order->get_items();
					
					$order_items = array();
					foreach((array)$items as $item){
						array_push($order_items, "'" . $item['product_id'] . "'");
					}
					echo implode(', ', $order_items);
					
					echo "]";
					
				?>,
				'ecomm_pagetype': 'purchase',
				'ecomm_totalvalue': <?php echo $order_total; ?>
		
		});
		</script>
		<?php
		}

		// For all other pages set the parameters for other.
		else{
		?>

		<script type="text/javascript">
			gtag('event', 'page_view', {
				'send_to': '<?php echo $adword_code;?>',
				'ecomm_pagetype': 'other'
			});
		</script>
		<?php	
				
		}
		
}

add_action('wp_footer', 'cp_dynamic_remarketing_tag');
	

Add to theme's function.php

Also make sure you have the gtag code in the header

<script async src="https://www.googletagmanager.com/gtag/js?id=AW-00000001"></script>
<script>
window.dataLayer = window.dataLayer \|\| [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
</script>