1. Navigate to the WordPress Dashboard > Preorders to see Pre-Order lists.

2. Click any of item to see detail view.

3. If pre-order is ready for shipping, you need to change order status for get payment.

4. Change status to Pending payment and update.

5. After customer payment complete, you can ship or deliver pre-order product.
6. You can see which order's contain pre-orders on Dashboard > WooCommerce > Orders.