In Operation Tonga, meet up with your new comrades.
Continue forward until you can give your second "command".
A few meters behind the truck, ontop of the cover boxes pick up the smoke grenades but don't use them now:
https://imgur.com/a/LztSsMEContinue forward until you navigate the truck into the mine field and jump out.
After walking through the dig give the command to push forward with the allied soldiers.
Right after giving the command throw your smoke grenades infront of the running soldiers for cover.
https://imgur.com/a/AW1PPjcAchievement will unlock immediately.