Your apprenticeship has been approved! Within a week of submitting the proper paperwork, Ryouta will receive a package from POKEGO. Inside the package will be a welcome letter from Professor Oak, his apprentice uniform (you can decide what it looks like based on the linked examples above), some textbooks, a pokeball for catching his starter Pokemon, and a piece of parchment paper and a calligraphy brush.

The parchment will have instructions indicating that Ryouta should write his tree code name on this paper when he's ready. Whenever he writes it down, the name will glow briefly before the parchment and brush disappear. From that point onward, the name he wrote on the parchment will feel as much like his name as Ryouta does.

Some specific notes:

Ryouta will have no issues with his background check! He will still be required to take a psychological eval, but it'll be a fairly normal one since he's sane just stupid.

Due to being relatively new to the paranormal (and stupid), Ryouta will have to take an additional course that will go over the basics about the Spirit Realm and the existence of magic. Since he's had some experience, this course will add a couple weeks to his apprenticeship if taken at a sane pace (though it will take less time should he decide to cram but please don't die).

Should everything go smoothly with his coursework (which his mentor will be the judge of), Ryouta will have his final assessment in December. His assessment will be oversaw by Professor Rowan, and it will consist of a written exam for general knowledge, a paper or presentation about social skills, and a practical exam that examines how well he's been working with his Pokemon (is he treating them well? Has he trained them? How do they work as a team? etc).

Should it not go smoothly, then his apprenticeship will continue until he's ready.

Good luck Ryouta!