You can access the data from woocommmerce cart object. Below an example code which takes a particular custom field value 

global $woocommerce;

$items = $woocommerce->cart->get_cart();

if (isset($cart['wcpa_data']) && is_array($cart['wcpa_data'])) {

    foreach ($cart['wcpa_data'] as $v) {

        if ($v['name'] = "select-1589385422376") { // change this name with your field name

            echo $v['value'];

        }

    }

}