Getting Hazel to act on external SSD

I'm struggling to get Hazel to act directly on an external SSD to auto rename files as I import them into new folders.
Maybe I'm looking in the wrong place for instructions in the manual?
I want them to have the name as per: number and date, is this possible? Thanks.

Can you provide more details?

OK: so I use an external SSD to import photos and videos to, when doing so I create a new folder for that shoot. As the files are imported I would like their names simply changed to number and folder name ( the folder name will be the location).

Are you able to throw any light on this, please?

What is the number? Just a counter? Before you mentioned a date but then mention using the folder name instead. I think a concrete example will help here. Include the folder structure, pointing out which part of the structure you need Hazel to monitor.

This is the gist of what I'm trying to achieve, Crucial being the external SSD:

You don't literally want the text "File number" prepended to the name, do you?

Also, it looks like you are trying to get Hazel to go into subfolders. Look it up in the manual as there's a chapter on how to do it. The important point is that you can't combine the logic into one rule like what you have here. You need to have separate logic for the folders you want to go into and the files you want Hazel to process.