So in heal harm for magnitude it says spent 2x force points to inrease number of targets effected by 1 for each rank purchased. So if i have 3 ranks purchased do i just spend the 2 points and effect the 3 extra targets or do i have to spend 2 extra points every extra person so it would be 6 points instead of two to effect 3.

Like it says on the tin: spend 2 pips and affect a number of additional targets equal to ranks in Magnitude. So 3 ranks = 3 additional targets for those 2 pips.

Note, if you had 2 more pips ( ) laying around, you could activate the upgrade a second time to affect 3 more targets (7 total), etc.