Generating file names based on the date from pdf

I stuck a bit with my code. The goal is to scrape Structured Data table from each pdf in Attachments folder and create separate excels files with date for each pdf. Very important: each file should have following naming convention: invoice number_debtorname.xlsx. Link below: GitHub - MichalOpala93/Invoice-Scrapping
Thank you for help in advance.

First you have to save the invoice number to variable let suppose (i.e InvNumber) then you used writeRange activity in file path you write that (InvNumber+"_"+ now.ToString(“ddMMyyyy”))