Every cell by default has an individual status of locked that can be toggled on
or off, BUT, that status does not come into effect until the sheet itself is
protected as well. So, you can either:-
Hit CTRL+A to select the entire sheet, then do Format / cells / protection /
untick the 'locked' option, and then simply reverse that for just the cells you
need to be locked and then protect the sheet, which will effectively protect
only the cells you have selected and turned on locked status for,
OR
Select just the cells you do NOT wish to be protected, do Format / cells /
protection / untick the locked option, and the protect the sheet. This will
UNprotect just the cells you selected
