Once you've made the TOC Sheet suggested by Paul, you might try this:
The TOC will actually be contained in a table on that sheet.
A copy of that table would likely work placed on any of the other sheets.
Consider laying out that table with the cells containing the links "stacked in rows, on top of each other, so that no scrolling ever has to be done," then placing a copy above the main table on each of the sheets.
Regards,
Barry
Note: I've not tested this, as I'm running an version of Numbers prior to the introduction of links that would move you to other sheets in the same document.
B.