I want to have a cell retrieve contents from another cell using the IF
function, but I need it to be variable. For instance, I want a cell to
receive contents from cell B2, if contents of another cell are A2, and if the
contents of that same cell are A3, then I want the B3 to show up, A4 - B4,
etc.

Is there a way to use a number placeholder like =IF($B$3=A$'x',B'x') where
'x' represents the number that I want to vary?

Thanks,