Add to API FAQ or Introduction use of PersistentID vs. Dataset or FileID in API Commands

[shlake]

Someone please edit the title of this issue.

Overview of the Feature Request Add more information on how API commands are composed. Help to make the examples more understandable and that in some cases an API command (example) uses a dataset and/or file ID and other times the persistentID is used. The syntax of the API is slightly different for these different uses.

What kind of user is the feature intended for? Improved documentation for API users

What inspired the request? Google Groups question (end of this thread: https://groups.google.com/g/dataverse-community/c/TqXmICwr0io?hl=en) and this NOTE from the guides: https://guides.dataverse.org/en/latest/api/dataaccess.html#basic-file-access

What existing behavior do you want changed? Let API users understand there is more than one way to write API commands especially when the documents may use either of the ways.