I imagine you are speaking about the last post which seems overkill to me. Why create a column (column E) of formulas to do the conditional formatting when you can apply the condition directly to the cells.
Maybe looking at some tutorials will help...
https://exceljet.net/conditional-for...-with-formulas
https://www.contextures.com/xlCondFormat03.html
https://www.ablebits.com/office-addi...matting-dates/
These are just a few tutorials pasted around the internet. We could retype these steps, but since they are already typed out and not exactly sure what you are understanding, there should help.