How I can use this sample size calculation formula

Hi Everyone,

Hope you are doing well!

I am launching a refugees and asylum seekers profiling exercises with the main objectives to determinate their poverty prevalence based on food and non food expenditures poverty line. I have 9670 households (targeted population) setted in the Capital and three refugees settlement (4 strates in total).
For our organisation, the formula should use is based on the average not proportion one (see attachment) because considering the fact that it is the first time that we are doing the same survey and we don't a prevalence percent before on their poverty indicator.
Unfortunately, I can't use this formula because I ignore exactly the value that I have to use for the different x value (u; d; etc.).
Can someone help me to understand how I can use this formula for my context ? Give an example for the use of the values of the formula ?