Nie

If it’s just NIE, then your original documentation will be checked, including passport and pre-sales invoice or other reason for having NIE (in Andalucia you now require a reason to have an NIE, such as house, car or other major purchase)  once this is complete, depending on the funcionario who attends you, you will either be given a letter there and then with your NIE, or told to come back in one to two weeks to collect that letter with NIE on.  If they tell you to come back, don’t argue - it will get you nowhere.

If you mean your TIE appointment, then the first actual appointment after documents are submitted and you have received you successful resolución, Whatever documentation you need to take (including probably Padrón and original passports) will be checked, and then your fingerprints from your right and left forefinger will be recorded electronically.  Your will also be required to submit your photo.

You will then be given a grey coloured letter that will bear a time and date on it.  This is the time and date of the appointment to collect your TIE cards.  Do not lose this letter, you will be required to present it on return.