You can program additional keys into a Fiat Cinquecento from 1995 to 1997 using a manual procedure. To do this you must be in possession of a red master key that starts the vehicle.
The key programming procedure is available here:
Fiat Cinquecento 1995-1997 key programming
If you do not have a master key then you will not be able to use this procedure.
Alternatively... if a key that starts the vehicle is brought or sent to us we have the facilities to copy the transponder chip within it onto a new one. The new key will then start the vehicle without any further programming being required. Email us at email@example.com for further information.