Hi,
Normally, there are several fields, and you save that in the hikashop_address table and then you just take the address_id and use it in the $order object with the attributes order_shipping_address_id and order_billing_address_id.
Now if you only have one field for the whole address, then either you want to split the address before doing what I just wrote above, or you want to create a custom field of the table "order" and of the type "text area", and save that address text in the custom field.