How to send emails automatically without entering in backoffice

[el_boda]

After making a sale, prepare the order and deliver it to the carrier, the carrier will send me the tracking number of that order.

With a connection to the API of the carrier I, update, automatically, the database table, via mysqli. The problem is that, if I don't enter, in the backoffice, in the specific order that has been updated with tracking number and click "save", the automatic email for the client with tracking number will not be sent.

Is there any way (coding a php file, making a cronjob, etc.) that I could send the emails of the updated orders without having to enter in the order, in the backoffice?

Thank you.