First and foremost, it's important that you understand the key difference here is regarding their hierarchy. City pages are considered a top level, whereas Neighborhood pages are considered a second level.
Here is a visual representation of the hierarchy:
Perhaps this hierarchy is best demonstrated via the Featured Areas page of your website (normally located at yourdomain.com/our-areas/)
And you will also be able to see related Areas/Neighborhoods/Developments in the sticky navigation bar, for example, if one Area has multiple Neighborhoods or Developments.
As you add Area/Neighborhood/Development pages to your website, you have the option to assign a Parent City (Top Level) for those pages. (For example: Which Area should the Neighborhood belong to)
Further Education:
Learn how to Add/Edit Areas, Neighborhoods, Developments, and also understand how to use all the features of the Neighborhood Guides: