Importing from csv file

Im trying to set up a template that clients can use to upload franchises. They will have over a hundred and individual additions vis the Add franchise button isnt an option.

I can see that when the Main Listing is added and ID number is created, which can then be added to the “franchise_of” on the spreadsheet. But when the client supplies the spreadsheet with all the new listing how do i advise the client what ID numbers to use for each new Place?

Ive attached a copy of a test sheet with details on, if someone could advise as to where im going wrong that would be fantastic.

Thanks