The first real stop on your journey in Famicon Detective Club: The Missing Heir is the Myoujin Train Station. After discovering a note that you had written in the Detectives office, you travel here hoping it will help you remember something.
After arriving at the ticket gate, select the Call/Engage option and speak with the Station Clerk. The Clerk is very helpful, and will answer number question. Select the Talk option the ask about the town of Myoujin, followed by the Ayashire family. He will point to a large mansion that they own nearby.
After that, a new Talk option will populate, where you can asked about the Ayashiro Family. Select that, then when the Clerk stops talking, select the “Ask him about myself” option. He will say that he has seen you before, and a new travel option will appear that allows you to travel to the Ayashiro residence.
Feel free to take that option and head for the residence where you can continue the investigation. You will need to return to the station later, after you have learned more about what is happening in the town, and some ancient legends of the area.