HI Folbo,
You also have two scroll bars in the right and bottom borders of the application window.
The length of each bar is shows the proportion of the height or width of the visible part of the document compared to the operating part of the Sheet on which this 'page' of the document sits.

Dragging the horizontal bar right will take you to the right edge of this sheet; dragging it to the left edge will then take you to the left edge of that sheet. Likewise up or down with the vertical bar.
A two-finger swipe on the track pad can also move you quickly across a tall or wide Sheet.
And in a Numbers Spreadsheet Document with several sheets and multiple tables on each Sheet, you can set up a single cell "Find me" table on each page, place a distinct keyword or phrase in =that table, and get to there from anywhere in the document to that table by pressing command-F, then typing the key phrase for that table into the Find box.
My code for this one was "TGT PGE". Numbers leapt to it when I had entered what is shown in the Find box.
Biggest issue with this is that the key phrase must be unique within the document. Find searches everywhere in the document, so if there are six eligible targets, the one you want might not be first on the list.
Regards,
Barry