Nissan 300ZX 1990 don't start with its battery but starts with a jumper from another car The battery voltage when the car is running is 10Volts. Is the voltage correct for this model what can be wrong?

Normal operating voltage should be close to 13.5. If you're only getting 10V, you need to replace the alternator and/or regulator. I'm not certain but usually the regulator is inside the alternator. If you can drive the vehicle to an auto parts retailer, you can probably have them test the charging system for you.