Hit 3 or i for Index. Define the page number listing. WordPerfect will then return you to the document. You will generate this in a moment. After generation, you should check the cross references to insure that they were updated correctly.
Possible mistakes occur around soft page breaks.
The Cross-referencing option allows you to refer to specific page numbers, graphic boxes, footnotes, endnotes, and outline numbers and it will automatically update the references when the Generate feature is used. The next prompt which appears depends on the choice you made in step number 4. A prompt will then appear which asks for a target name. This name will be saved with both the target and the reference so that a match can be made later when the references are updated. Hit y because you will want to save each of the individual subdocuments.