Read data from firebase as GridView

Hi guys. I’m stuck. I have firebase realtime data base.

I want to sort the data, summary it and send it to the another person as GridView (table) every day- as mail or pdf or excel.
The data are different- for example somethime I have 1 issue, sometime 4 issues, so its not constant value. What is the best and the simplest way to do that? Collection View, TableView or something else?

Stay safe!