Here's how to multiply an entire spreadsheet by 1000 without going into each cell:

1. Select all the cells in the spreadsheet by clicking on the top-left corner of the sheet (where the row and column headers meet).
2. Right-click on any of the selected cells and choose "Format Cells" from the context menu.
3. In the "Format Cells" dialog box, go to the "Number" tab and select "Custom" from the list on the left.
4. In the "Type" field, enter
   Formula:

   "0;;;" 

   . This will format the cells to display nothing, but still retain the values.
5. Click "OK" to close the dialog box and apply the formatting to the selected cells.
6. In an empty cell, enter the number 1000.
7. Copy the cell with the number 1000.
8. Right-click on the top-left corner of the sheet again and choose "Paste Special" from the context menu.
9. In the "Paste Special" dialog box, select "Multiply" under "Operation".
10. Click "OK" to close the dialog box and apply the multiplication to the selected cells.

That's it! Your entire spreadsheet should now be multiplied by 1000 without going into each cell. The values will still be there, but they will be formatted to display nothing. If you need to see the values again, you can simply change the cell format back to a number format.