find the customer date of the orders that have the status" delivered" | did you mean the order date? | yes
SELECT t2.order_date FROM customers AS t1 JOIN customer_orders AS t2 ON t1.customer_id   =   t2.customer_id WHERE order_status   =   "Delivered"
customer date of the orders refers to order_date; status 'delivered' refers to order_status = 'Delivered'; joining customers with customer_orders on customer_id;