My point is if you follow the simple rule of thumb of a small pump with a large filter, you will have an energy efficient pool with good filtering capability. The operating point of the pump with the plumbing might be of some interest but it really shouldn't be the key metric when determining which pump and filter to get. The more important factors are the size and efficiency of the pump and the size of the filter.
However, if you really want to determine head loss, you have understand that it is a very difficult and time consuming process. You must know the length and diameter of every pipe and a count of every fitting and valve even for the parts underground. Fittings and valves are the largest contributors to head loss and without an accurate count, you have to guess. Also, head loss in plumbing is dependent on flow rates which in turn are dependent on the pump's head curve so you have to solve both the pump head curve equation with the plumbing equation to find the unique operating point.
In my signature, there are some pump tools which allow you to estimate flow rates and energy costs for many different pool pumps. These tools use approximations for the plumbing system which will get you fairly close without having to know all the aspects of your pool plumbing.