Find multiple cells containing same string in different excel files

Hey, I am kinda new in the powershell game and got a question regarding comparing cells between two excel files and extracting those that contain a certain string.

So it is like this, we have one file with names of cities in our country and it is sorted by alphabetical order and one with all of the e-mailadresses that exist in their domain.

What we want to do is take the city that is first, in the first excel document and compare it to the other document and extract all the adresses that contain the name of that city somewhere in the adress.

For example, in the first cell in the first document we have Atlanta, we want it to take Atlanta and search through the second document and extract all mailadresses containing Atlanta in them like “info.atlanta@domain.com” or “Atlanta@domain.com” to a new third document

I hope you understand what I mean and can help me, thanks in advance!