Ezek az autók would be these are the cars

Ezek autók. = These are cars.

ezek az autók = these cars (and also: these are the cars)

"Kocsi" can be used for "car", but it has other meanings, as well. Originally it was a horse-drawn carriage, and that meaning is still alive in Hungary. But in the general usage it means car.

https://en.wikipedia.org/wiki/Coach_(carriage)

kocsi is the Hungarian word from the town of Kocs - and gave us the English "coach" etc. Autó is a more modern "international" word and applies only to modern automobiles ie not coaches