Hello @Raskolnikova ,
Welcome to the community!
Every phone has a unique unock code, you will need to contact customer service and they can generate the unlock code for your phone.
You will have to provide the IMEI number for the phone you can get that by going tot he phone settings then about phone and it should be in there or from the dialpad you can type *#06# and it should display the IMEI number.
You can contact Fido customer service from any of the available methods listed here.