How to make a city state field as a dropdown field in account object

Summary:

Content (please ensure you mask any confidential information):

Hi Team,

In the Account object in Redwood Sales, we have address fields such as Address Line 1, Address Line 2, City, State, and Postal Code.

We would like to make the City, State, and Postal Code fields dropdowns, but without using the Manage Geography Address Validation feature.

Version (include the version you are using, if applicable):

25D

Code Snippet (add any code snippets that support your topic, if applicable):