Before you get to edit file option, I would recommend you play with the creation of users and shares as well as how to restrict access, RO and RW. It is simple and easy once you get the hand of it. No need to create one per user as well, just create one share and add users to it, each user can have different access as well for the same share.
Once you fully understand how that works, if that does not solves your issue, then go for it.
Now, not sure if you are also referring to Mobile apps, if you need those, there is no other option but the “public” folder as far as I know.
