how to delete indivudal cells

[tweacle]

I found this macro that delete entire rows if cells in column B are empty.

 Sub Deleterows() 

Dim lr As Long, i As Long 

lr = Cells(Rows.Count, "A").End(xlUp).Row 

For i = lr To 1 Step -1 
If Cells(i, "B") = "" Then Rows(i).EntireRow.Delete 
Next i 

End Sub

Can someone advise me if I have this correct if I want to delete CELLS in row "M"

Sub Deleterows() 

Dim lr As Long, i As Long 

lr = Cells(Rows.Count, "A").End(xlUp).Row 

For i = lr To 1 Step -1 
If Cells(i, "M") = "" Then Rows(i).cells.Delete 
Next i 

End Sub

Also is someone able to advise me on how to repeat it right the way down the workbook until last entry.
Thanks