Running A Loop On A Few Columns Simultaneously

I am trying to run a loop on a few columns simultaneously, from the last row to the top (well, until the 2nd row).

So I have a few columns of data, A through I, and the number of rows they populate changes all the time.

So how would I run a loop that will check for the following:

If a certain row in Column F is greater than the previous row in column F by 1.5times, then in that same row, if number in Column B is greater than number in E, the code should put the the value of E in a new column, lets say M (in the same row)

I know that sounds very confusing, but is that even possible? I am playing with loops, and I can only do very simple loops where I define a range, like