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This is storyrelated, so you can't miss it. You will get this achievement right after your very first mission, before you can customize your character.
The mission itself is very easy, since it's more like a tutorial and you don't take that much damage.
When you have to fight the enemies on the roof and the helicopter, shoot the ventilator shaft when enough people standing next to them. Here's a video to show the fight
credits go to: OpTiCxFuZiOnz