Adding data in datatable

Hi All,

I need to read all the excels placed in the folder and consolidate .Each excel will be having 10+ excel sheets .I have to consolidate sheet named “x” from “g4:g15” and place it in folder .
I want to add columns to differentiate them based on date mentioned in excel instead of appending.Columns needs to be generated dynamically based on number of excel sheets

My output must look like this

Please help .Excelsample