Please keep in mind that Tracking displays only for orders that were already placed on AliExpress and got AliExpress order IDs. To get started, go to WooCommerce => Orders.
You can sync all orders having AliExpress order IDs, just click Tracking Sync All button. It syncs all such orders one by one. If no orders have the AliExpress order ID, then that button is not shown. If you want to sync the specific order only, click on the refresh icon near it.
Once sync is done, you can click the i icon near synced orders and view the tracking codes. The information is shown in the pop-up window.
How to edit Tracking Codes and AliExpress Order ID?
If you want to edit tracking codes or AliExpress order ID, you need to open Order Edit page. Click the pencil icon to edit the values and use Delete codes link to remove them.