Have you tried Preview, provided with the Mac OS? It will open your images, allow you to view metadata, then export (I think you meant export, not import) to another location. I am not certain how you would export to iCloud (you might need to import them into iCloud). Then you could import your photos into Aperture from wherever Aperture allows this to be done (I do not use that application, and I use iCloud primarily for syncing contacts and calendars).
Select file, right click, and choose Preview to open.
Select files in Preview, then File, Export. Note that selecting photos in Preview is not the same as tagging them - the selection is ephemeral.
For Metadata, go to Tools, Show Inspector, then select desired menu item - General, Exif, GPS, etc.