How to get ADHD medication with abroad diagnosis?

Basically, we moved to Japan back in June. Early this year I got diagnosed in my country with adult ADHD (basically runs in the family) I got the documents but I never really got the medicine since 1) I didn't have a family doctor at the time to go over best options / treatments 2) decided to try to manage without medication (which is not working)

If anybody knows how I should go about this please help out it's really appreciate it.

Thank you 🙏

by Pretend_Afternoon885