Perform same action on similar files and create one master list

I have multiple files of the same kind (same headlines, different length of list). Files are at CSV format at the time, in contrary to the attached file that was converted to xlsx.
I would like each list to leave only the 5 left hand side columns, add another column with the file name (only file name, no full directory, and better without dashes).
Afterwards, I'd like to create a continuous table (consolidate?) of the multiple lists I got.
attached an example of stage one of the process.

Gratitude to all helpers.
Droriley.

members_702309_end-makers.xlsx

Originally Posted by Droriley

I have multiple files of the same kind (same headlines, different length of list). Files are at CSV format at the time, in contrary to the attached file that was converted to xlsx.
I would like each list to leave only the 5 left hand side columns, add another column with the file name (only file name, no full directory, and better without dashes).
Afterwards, I'd like to create a continuous table (consolidate?) of the multiple lists I got.
attached an example of stage one of the process.

Gratitude to all helpers.
Droriley.

Attachment 383209

what do you mean by "5 left hand side columns"

Originally Posted by Mehdi Farrokh

what do you mean by "5 left hand side columns"

I mean the following columns to remain:

Email Address First Name Last Name Company Country

And to them I'd like to add a column named "Group" with the same entry for each of the lines.

So.. the filenames are always delimited by an underscore?

And you want the upper bound of that split( as shown by "end makers" in your example) to be shown in the new column (column F)?

Where are your files? DO you want a Folder picker dialogue so the user can select the Folder where they are?

Perhaps (for testing purposes).. attach maybe 3 of the csv files (change the file extension to .txt to get bypass any automatic conversion)..

Originally Posted by apo

So.. the filenames are always delimited by an underscore? Correct

And you want the upper bound of that split( as shown by "end makers" in your example) to be shown in the new column (column F)? Correct

Where are your files? DO you want a Folder picker dialogue so the user can select the Folder where they are? Not sure what you mean - I'll make a separate folder for all relevant files.

Perhaps (for testing purposes).. attach maybe 3 of the csv files (change the file extension to .txt to get bypass any automatic conversion)..

Please find attached 3 CSV files, (one which you'll be able to see origin in first 8 lines and target look from line 24. In reality only lines 1-8 (or 1->any number) exist. also please find file called "Master list". This is the final goal. Cheers!