As the years passed by the number of Pokemon begun slowly decreasing which lead to many changes. One of the major ones were changing rules of registering as a Pokemon trainer. The rules became strict and the violators of the rules were punished severely.
Finally in year 2013. a new constitution was brought and some of the following rules were brought together with it:
From that point further you had to be 16 years old to start your journey as a Pokemon trainer.
If you did not already aquire a starter Pokemon, you can be given one of the starter Pokemons of your region.
As a trainer without an academy you are allowed to catch up to 5 Pokemon. Catching more Pokemon without being admitted to the Pokemon Academy ( PA ) is strictly forbidden.
You can apply to join the PA at the age of 18 by entering a written exam and a battle test.
By gaining access to the Academy you are given the opportunity to catch 5 more Pokemon during the 2 years that the Academy lasts. The first one teaching general knowledge and the second year reserved for specialization.
After getting the Academy certificat you become a professional Pokemon trainer and you do not have a limited number of Pokemon you can catch.
So, you have been admitted to the PA, meaning you passed both the written exam and the battle test.
You now have the ability to catch 5 more Pokemon, bringing the number of caught Pokemon to the number of 10.
That does not guarantee you will successfully finish the Academy.
But good luck through the rounds of this contest ;)