This achievment is obtained during the progress of the campaign and so cannot be skipped. The easiest way to this achievment would obviously to set the difficulty to lowest on your playthrough. The mission you obtain this is upon completion of the "Wolverines!" level.
For people looking for a challenge here is a handy veteren guide for the entire "Wolverines!" mission. Please note there are plenty of other Youtube veteren guides and even if you are doing a lower difficulty these tips and stratagies can still help effectively.