why do we need cars when we can fly aircraft instead? I mean we can use aircraft to fly across the planet and cars can only get you some place on the road:/

Aircrafts are more complicated, they take more time to prepare. If you're wondering why, you'd need to prepare wing length, body weight, shutters, seats, and turbulence control. Aircrafts will need runways, more experience, etc.

So expense-wise, aircrafts are more expensive, you will only need to buy a car once, think about private-jets, they will be much more expensive than a simple and functional car.

Additionally, cars are more straightforward and take less time to build, See More they're easier to control and will cause less damage upon accidents. (Aircraft crashes are usually catastrophes.)

I understand that you can use Aircraft to take short cuts and even fly overseas, but overall, cars would be a more practical choice.
Hope I helped!

if everyone used aircrafts,the skies would turn out much like the roads. Plus aircrafts take far longer to make and are harder to learn to use