The Journey is FIFA 17's story mode where you follow Alex Hunter from a young age in the academy to the big leagues. It's an easy achievement but fairly time consuming. I recommend putting the settings to lowest difficulty and 4 minute halves to make it go faster.
You start off by completing a six-stage exit trial before picking your Premiership team. You'll make a lot of substitute appearances before eventually being loaned out to either Norwich, Aston Villa or Newcastle. You'll spend the majority of your time here building a reputation for yourself. Towards the end of the season you'll be recalled to your Premiership side to finish off the campaign. Your final match is the FA Cup Final against your biggest rival, where your childhood friend will be playing.
I figured I'd drop a few notes in case anyone was wondering about this game mode. I'm unsure if you can fail The Journey by playing poorly and losing your spot in the starting line-up. I would assume you need to play fairly well throughout to reach all the milestones to progress the story.