This trophy is called "
The path that we take will become Panzerfahren!" which requires you to complete all Beginner's Training.
This is a "story" (these are actually part of the Extra Match mode) based trophy and is unmissable. There are a total of four Beginner's Training that must be completed to unlock the trophy, and you're unable to skip them as the game locks you out of everything until completing them.
The missions are pretty straight forward and I'll give a quick breakdown of them.
Beginner's Training/Lecture - As soon as you press the Start Button on the title screen, this begins to play. It's the sensha-dō informational video seen in the Girls und Panzer anime.
Beginner's Training/Movement - Use the Left Stick (
) and drive forward into the visible check points.
Beginner's Training/Battle - Use R2 (
) to shoot and destroy the two enemy tanks. You will earn the following trophy for certain:
You can also quickly earn the following trophies:
Beginner's Training/Practical - Drive around the map and destroy the two enemy tanks.
Upon defeating the second tank, Beginner's Training/Practical will be completed and the trophy will unlock once the Victory Results screen loads.
Here is my game play video covering the four training matches and then the first story battle: