There were cars well before World War 2. Before World War 1 even.
All passenger cars
Yes, there were.
Yes, almost every country in the world had cars by WW2.
World War 2 cars were much tougher than today's cars, and today's cars can go much faster, there are more differences to them too so these aren't the only two differences.
car manufacture was suspended during war
PROBOBLY because we defeated them in World War 2
No.
Any body that could or wanted to.
yes
During World war 2 they used trains, trams, buses few people had cars as they were not affordable.
They were mostly used for the transportation of Jews to and from concentration camps during the Holocaust, which was during World War 2.