Welcome to Part 2!
As mentioned, you (Young ERP Consultant) are a paradox. You are a knowledge worker in the ever-expanding information economy. Also, you don't know anything.
The solution seems straightforward: Learn. Go know something.
But what to learn? Where to start? The universe of things-to-know is ever-expanding. One ERP example: Microsoft Dynamics is serviced by some 10,000 Microsoft employees. Microsoft's ability to build new functionality is orders of magnitude larger than your ability to learn new functionality.
Advice Part 2: Use a T-shaped Learning Approach
What does that mean? Develop a shallow understanding of your ERP system at large, as well as deep knowledge of a very specific part of the system.
Broad, Shallow, Horizontal Learning
ERP is an integrated system, so you need a general understanding how different parts of your system connect. Appreciate how changes in one process or module affect other processes or modules. Subledgers post into ledgers, yada yada yada. (This is the horizontal part of the T)
Narrow, Deep, Vertical Learning
Pick a discrete, niche topic and study it intently. Learn it at a deep level - not just a sales demo of what happens when everything preconfigured goes right, but what things can go wrong? How do you fix them? What are those extra parameters nobody uses and why? (This is the vertical part of the T)
Surprisingly, if you pick a narrow enough topic you can know it better than the average consultant in just a few days. Study a bit more and...Congratulations! you're an expert.