Need help with conditional formatting.

Hello,

I need to have my spreadsheet enter a date that is 6 months (180 days) from an original date once it is entered. I have 2 columns - Date Placed and End Date. I need my spreadsheet to auto populate a date in the End Date column once I place a date in the Date Place column. Also I need the cells that do not have a date entered into the Date Placed column to remain blank until one is entered.

Thank you!