Protect a Worksheet from Editing
Click on the “Review” tab on the main Excel ribbon. Click “Protect Sheet.” Enter the password you would like to use to unlock the sheet in the future. Re-enter the password you made to confirm that you remember it and then click “OK.”
Also know, how do you make an Excel document not editable?
Select the whole worksheet, Right Click->Format Cells->Protection, uncheck the “Locked” check box. Select the column you want to protect, right Click->Format Cells->Protection, select the “Locked” check box.