Juan's car. Car of Juan
When we are talking of Juan's belongings (for example).When we put "Juan's"and when we put "of Juan".Example: =This is Juan's car. =This car is of Juan.

Question

Juan's car. Car of Juan
When we are talking of Juan's belongings (for example).When we put "Juan's"and when we put "of Juan".Example: =This is Juan's car.  =This car is of Juan.

Answer

In English when something belongs to somebody we add  's  to the end of the proper noun.
The sentence 'This is Juan's car is correct.
'This is the car of Juan' is grammatically incorrect in English.

Answer

Using " 's possession" is more recommended for animate nouns when it implies one of the below:
-Possession: like Juan's Car
-Attributes: like Juan's black hair
-Association: like Juan's neighborhood.