Bulletin Board

Hello.

I need a principle like this:

when submitting an announcement, the user initially selects a geographical area, after which a list of cities belonging to the previously selected area should appear. I did it as follows: I added a vocabulary for Area in the taxonomy, and in the list of terms, I added the areas that I need. In the field management, I added cities to each area. However, when adding content, the selection of the area is available, but the selection of cities does not pop up afterwards.