Insert rows and enter data in blank cells.

Hello :-) I am trying to put together a macro and I am stuck!!!

I need to add 3 rows at each change in the data in column C. Within those new rows I need some rows to fill down and some to enter new text and some to enter a formula.

I have attached the example with a before and after tab.

The data in yellow on the "after" tab will be a vlookup formula to another workbook and the data in green will be a formula. Otherwise the data will either fill down or will be specific data as shown.