Add Custom Field to Cart Item

function add_custom_field_to_cart_item( $cart_item_data, $product_id, $variation_id ) {
    $custom_field = filter_input( INPUT_POST, 'custom_field' );
    if ( ! empty( $custom_field ) ) {
        $cart_item_data['custom_field'] = $custom_field;
    }
    return $cart_item_data;
}
add_filter( 'woocommerce_add_cart_item_data', 'add_custom_field_to_cart_item', 10, 3 );

function display_custom_field_in_cart( $item_data, $cart_item ) {
    if ( isset( $cart_item['custom_field'] ) ) {
        $item_data[] = array(
            'key'     => 'Custom Field',
            'value'   => wc_clean( $cart_item['custom_field'] ),
            'display' => '',
        );
    }
    return $item_data;
}
add_filter( 'woocommerce_get_item_data', 'display_custom_field_in_cart', 10, 2 );