Approaching understanding a huge project
About 4 months ago I graduated college with my BS in Computer Engineering. I just started my first real job as a Software Engineer. I have worked in the field on a few internships, but this job presents some interesting challenges.
My main question is this. I just got plopped into this massive project where There will be an enhancement for me to implement(currently in design phases). So for now my manager told me to just go look over the code. Is there any system or process that anyone uses to approach understanding a large program? Also, is this typical first couple week activity for a new employee? Please feel free to share any first week stories.