Rename, then Combine and then do some operations on .csv/.excel Files

One of my client purchase data from a company → The data is the domain registered with details such as Name, email, Phone etc. The details are divided into folders based on countries such as → Australia New Zealand USA UK Ireland and all other Countries. In this country Folder, a file is kept, which is normally of the sort [login to view URL] that means the name is same in all the folders [login to view URL], for example. See this Video → [login to view URL] Operation 1→ Change the name of the file, which is CSV or excel sort of format to country format such. Precisely this image → [login to view URL], but you have to make it in such a manner that it can handle any extension in excel. For example, in Australia folder, the "[login to view URL] or [login to view URL]" should be changed to [login to view URL] and in zimbabwe folder, it should be changed to zimbabwe_1.csv. Similarly for other countries. Then collect these modified names extension in one folder named common. Got It? Operation 2 → Combine all the modified Files into one big File. I am showing you structure of the sample [login to view URL] file see this video → [login to view URL] We will need 3 columns to be combined = Domain Name, Full Name, and Email. While doing this combination it will be advisable If 4th column can be created which will have entry like from where the entry is coming such as Australia_1, Zimbabwe_1 Operation 3 → Concatenation result in a new column like this → Full Name <Email> that means name and email concatenated in the above format that I showed you.