PokéBucks/Money

PokéBucks, commonly just referred to as money and sometimes shortened to a simple P or, is the currency used in Pokémon Planet. It is earned during battles with Trainers and wild Pokémon. The higher level of the enemy Pokémon, the more PokéBucks is earned. The easiest and safest way to earn PokéBucks would be teaching your Pokémon a powerful move and grinding by battling wild Pokémon repeatedly.

there are a lot of places in the game where you can get stuck because you don't have enough money including the kanto safari zone