The answer to this question is a huge “it depends”. Without knowing the particulars of your application’s needs it will be hard to provide a concrete answer.
To answer your question: Yes, you can use SQLite or Core Data, typically the latter makes it easier and there is little performance gains for small amounts of data. Plus you have the ability to sync.
There are many ways to store and retrieve data for iOS/Swift (such as Core Data, SQLite, Firebase, CouchBase, JSON/resource or retrieved, PLIST/resource or retrieved, shared file/static, etc). Each one has advantages and disadvantages that go beyond the scope of this humble reply.
If you want to populate a drop-down for dynamic fill, please ask yourself if this data changes, how often and how? Depending on that, you may want to use different methods, each one being more efficient for your purpose.
Please note that in a traditional server side model, you have a similar situation, but tend to stick with what you know best (such as MySQL), but other (better?) solutions may be available such as NoSQL (Mongo, Redis, etc) or other SQL (SQLServer, Postgresql, etc). But since the resources are all in one spot, it doesn’t matter as much.
This is not the case with your mobile device, as you may not always be connected to your resource via network, or it may be slow, etc.
The best recommendation anybody can give you is to learn about your options, and pick the best tool for the job.