When the cell is filled with value, automatically update the value in other cell

Hi,

I am filling in C8 based on which the J8 should set the default value as "NOt done". I hvae done this using formula in cell J8 but it goes of if we delete it.

This should be repeated till row no 100.
for example if i fill c100 then similarly J100 should be not done

How to write macro for this.