At first, no owner opened the door,

The chance of not getting a car is 66%

Whether you choose the winning car or not.

The host will open the door with a goat.

So I think it has no effect on the probability of the first choice.

The chance of getting a car by changing doors is equal to the chance of not getting a car the first time.

It should mean something like this.

But I think it's too far-fetched

Personally, I think the odds will be 50-50.