Its a normal old everyday OBD2 code reader/scanner. It will only talk to the engine computer (DME) on your car. Appears to only display the trouble codes (Pxxxx) and not any of the PID information like the fuel trims. So it will give you the codes but not the details needed for the full diagnosis.
If you have the OBD2 plug under the steering wheel, then you will not need any other plugs or connectors. If you only have the 20 pin "Pac Man" port under the bonnet/hood, then you will need a adapter to go from OBD2 to the 20 pin port. Plenty of these on E-bay etc.
If you want to talk to other modules on your car, have a read of this thread.
https://zroadster.org/threads/how-to-scan-early-model-z3s-pre-build-date-03-98.39937/