For making this cleared, with this case, you should follow this instruction so when you got order placed, the tracking code number will be sent to your customer.
Go to Ali Orders Dashboard > Orders List > Orders Settings
Make sure, the box "Send notification email to customers about the order fulfillment" is checked.
Beside that, you can put the tracking website where you usually use, it will be included in the email as well. These website might be:
Then you can simply save settings.
When you got new orders placed again, it will be sent to your customer automatically.