If they are usable files, drop them directly into “Content” while the project is open THROUGH UE5, don’t use Windows Explorer or Macintosh Finder for it as it can cause issues. 
That being said I don’t know what you’ve extracted and the extensions for them, if you drop those here I might be able to tell you if they can drop directly in, or if you need to put them in another program first and re-export them as a different file type (For instance, sound works best as .wav).