I there I have placed the wrong shipping address how do I fix it

For an order from the Apple Store online? If so, see information in https://www.apple.com/shop/help/viewing_changing_orders

including the following:

Edit Shipping Address

If your order is in Processing, you may be able to edit your shipping address in your order details. In the “Delivers to” section below your item, select Edit.

To edit your default shipping address for future orders, select Shipping and Billing in the Settings section on the Your Account page.