OK. you need to go back a step or two...
I assume you have (or need to have) a process as follows:
Get Rows (from excel worksheet)
For Each Row
Get required fields (columns)
Process fields for conditions, changes, etc
Write CSV row
Loop
...
End
I'm guessing you've got the "Get Rows" bit as that is probably returning the "list of Items" and Values fields you are seeing.
So you need a "loop" (for each...) to cycle through each row in the file (data set).
After your "get Rows" action you need an "Apply to Each" action which takes a single input value, and you should put the "value" object there.
Now within the "Apply to Each" block you can put your actual field processing, and its here that you will then see a long list of available objects, including "Requested By", etc.
At some point you're going to have a "write record" action of some sort. If you're writing a CSV file this may just be a long string varaible to which you append each field in turn. In this field or in a field item in an action, you would then use the "object" from the source file however you wish, such as: replace(<requested by object>,',','')
Good luck!
