Searching the internet for public serial numbers or activation keys poses severe security risks:
The most legitimate way to use this version today is through specialized, older software repositories that provide authorized legacy access or by finding a version that does not require online activation. The Evolution: Borland to Embarcadero
The built-in utility found in the /Bin directory of the installation path. It generates a "request code" based on your hardware profile and provides a field to enter the corresponding "activation key."