The wrong anti-freeze could cause the water to freeze in the engine. The wrong anti-freeze could cause abnormal corrosion in the radiator.
Volkswagen or any other vehicle shouldn't use any antifreeze. If any car is using antifreeze something is wrong.
Lack of antifreeze or wrong mix of antifreeze and water.
You spelled "beetle" wrong.
Leek.
You can not. The two cars are completely different...the New Beetle has the engine at the wrong end. The New Beetle is bigger than the Old.
Nothing Nothing
The headgasket has failed.
Your heater core has failed.
It will overheat and cause damage
I would recommend you drain it out, flush the system, and install the correct green coolant that Ford recommends. Using the wrong coolant can damage parts.
You probably used the wrong type of antifreeze. You should use the type for aluminum heads.
Head gasket could be bad