Confidential, the closest thing to what you're looking for, as I see it,
would be to hide all the rows below a certain point. Select all the rows you
wish to hide, then Format > Row > Hide. That creates the illusion that the
worksheet ends at that point.
What I am trying to achieve is so that, I have a spreadsheet set up, however
I don't want people to be able to scroll down the page past row 37 or column
N as there is no need for them to!
Righto, Confidential. In that case you'll probably want to hide everything
below Row 37 and everything to the right of Column N.
Alternatively, you can hide any formulas you don't want people to see and
lock cells you don't want people to change, then protect the worksheet. See
Format > Cells > Protection and Tools > Protection > Protect Sheet.
Of course, you can both hide columns and rows and protect the worksheet.