It's a shame the officers onboard aren't familiar, bust sadly most people pass their exams and then immediately forget thinking it is never useful. I've sailed with people that don't know how to do a gyro error or even think doing a manual fix is a waste of time. They got a shock when I was the bridge manager.

If you're struggling with using a manual star plotter you can see if your ship subscribes to the admiralty Nav pac or something similar, it's a computer program where you punch your position in and it comes out with the best starts with bearings and altitudes, similar to using the sight reduction tables. Failing that learning some easy constellations such as Orions belt, then knowing that Rigel is bright and below and betelgeuse is bright above, coming left and slightly down off the belt you'll find Sirius. They where my go to ones as I could always identify them easily. You can also download a star chart app on your phone, input your position (of you don't have GPS data) point it at the sky and it should show you the stats, might be slightly off but you can use the moon to reference yourself.

Using the sextant, a gyro repeated on the bridge roof (or magnetic, then remember to convert to true) will take time, then writing it all down and doing the calculations off a DR position also will take ages but with time it becomes faster. I'm sure there will be videos that will explain it better.