A simple way is to write the formulas into the sheet for testing purposes first.
C2: =A2<TODAY()
D2: =A2<EDATE(TODAY(),3)
E2: =A2<EDATE(TODAY(),12)
drag down. As you see if the formula returns TRUE the cell is formatted.
There is no need for a green condition, format all cells with green by default. Use the same formulas inside the conditional formatting.
Andreas.