How can I define a scroll area?

My calc-list sheet extends from A1 to AF403.
I would like to reduce the scroll area to the sheet.

I don’t actually understand “to the sheet”, and assume you want to address the used area.
-1- Goto cell AG404 and hit Shift+Ctrl+RightArrow.
-2- Rightclick on one of the selected column labels.
-3- Slect ‘Hide’ from the context menu.
-4- Do respectively for the rows below number 403 using Shift+Ctrl+DownArrow and the label of a selected row.

Hi Lupp. thanks a lot. It worked.