Adding custom information in the cart item

functions.php

<?php

/* Adding the custom infromation in the cart item */
function add_custom_info_to_cart_item( $cart_item_meta, $product_id ) {

	$cart_item_meta['custom_information'] = 'This is my <strong>custom</strong> information.<br> Please contact support for more information';

	return $cart_item_meta;
}
add_filter( 'woocommerce_add_cart_item_data', 'add_custom_info_to_cart_item', 25, 2 );

/* Displaying the custom infroamtion in the cart table */
function show_custom_info_to_cart_item( $other_data, $cart_item ) {

	if ( isset( $cart_item['custom_information'] ) ) {
		$other_data[] = array(
			'name'    => __( 'My Custom Information', 'domain' ),
			'display' => $cart_item['custom_information'],
		);
	}

	return $other_data;
}
add_filter( 'woocommerce_get_item_data', 'show_custom_info_to_cart_item', 25, 2 );