EMF is the maximum potential difference between 2 electrodes,when no current is drawn from the cell.Does this mean that the cell is not in use or all the free electrons have perished?

Actually the term EMF is developed to suggest the total potential diffference which a cell can provide

given that the internal resistance of the cell is ignored.

ZTo ignore the potential drop across the internal resistance we have to consider the assumption that the current drawn from the cell is zero, i.e is no current passes through the intrnal resistance of cell.