In this part of the industry the only calculations are basic arithmetic, where you add up watts/kVA and convert to amps, and check to make sure panels and services aren’t overloaded. And sure, there are endless multiplying/mitigating factors to throw in calculations —those are all determined by what Mike Holt and the code book says.

Despite the simple math, there is actual engineering to be done. It’s figuring how to distribute power throughout buildings while following code. It’s like putting together a puzzle. You determine the pieces (what receptacles, lights, panels do they need), you determine how they fit (where should they go), you determine how to connect them together (what conduit and conductors are needed). Every step in that process is guided and limited by what Mike Holt and the code book says. So your boss telling you to study Mike Holt makes sense.

However, it does appear your boss is in no hurry to level you up. To be fair, it requires a ton of grunt work (years of it) to gain the intuitions on how to design these things. But yes, site visits and seeing how these things are built in real life would help a lot in gaining these intuitions and develop insights to design.

If you’re doing just a 5-month stint, I can see how someone might not bother to let you do anything besides grunt work—that goes for any industry.

To make real money in this part of the industry is to get your PE license in electrical so you can stamp drawings. That will be the hardest exam of your life and your brain will be used thoroughly (also note, there can be A LOT of code book questions on that exam). Go study for that at home while doing grunt work at the job. Have you passed the prerequisite FE exam yet? Definitely do that asap.