Apple Works, and previously Claris Works files cannot be opened in any current version of iWorks (Pages, Numbers, Keynote)
Fortunately there is a way to convert those old files to a format which can at least be opened.
Libre Office is available as a free download and will open many file types including Claris/Apple works files
Once opened they can then be saved out in another format which can be read by other programs such as Microsoft Word, Excel etc.
Libre Office Download (Free)
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