Explanation
If you have an existing knowledge base and you would like to migrate that content into a knowledge base, you must create specific Content Types for that content to migrate to.
Before you migrate your knowledge base, create the following Content Types:
C: HTML - These answers represent HTML content. You create an HTML article by entering text in the Summary, Question, and Answer fields on the Add Content page.
D: URL - These answers represent URLs to external content. You create a URL article by entering the URL of the document that is to be the answer source for the given question in the URL field of the Add Content page.
The URL must be to one specific page and not to a page containing links to additional sources or external collections. It is also important to enter a descriptive Summary and Question as Knowledge Advanced uses the information in these two fields when conducting internal searches for documents. For customer searches, Knowledge Advanced also indexes the destination URL so it can be searched.
E: Attachment - These answers represent standalone documents attached to the answer. You create an attachment article, select the attachment to use from the Attachment link on the Add Content page.
FAQ - These answers represent frequently asked questions.
KCS - These answers represent similar content from KSC articles.
Manual - These answers represent application manuals.
References:
https://docs.oracle.com/cloud/may2017/servicecs_gs/FAUKA/Content_Authoring.htm#FAUKAcontent_authorin