Google sheet formulas edited

I am looking for assistance in editing Google sheet formulas. Specifically, I need help editing Sum formulas, Average formulas, and Vlookup formulas. The formula I would like to be edited is =IMPORTRANGE("https://docs.google.com/spreadsheets/edit"," Back-up'!B36"). I am open to suggestions on changes to the formula, so creativity is encouraged. I need this task to be completed within a week. If you feel you fit the criteria then I am interested in hearing from you.