Creating or modifying a user account that has no rights

Hello.

I need help on creating or modifying a user account that has no rights.
I need the computer to be on and the user can't do anything other than shutdown the computer and use a program. The computer has a specific program that we use on our company and that should be the only thing the user can use. Windows Key shortcuts disabled, no access to the task manager, nothing, just our program and the shutdown key on the start menu. I really need this to avoid users to damage the program or the computer itself.
Is this possible?

Sorry if I'm posting this in the wrong section.

Thanks in advance.

Is this on a domain or local? There is a programmer feronics deep freeze which protects the PC even if you delete windows files or anything else on reboot it will all be back safe

Isn't the stock on a server? The program can have exceptions set so can keep stock records

You might look into setting up a Thin Client with Citrix Receiver installed, and then giving them only the access they need via Citrix Receiver.

In this scenario, the user would be using a thin client, not an actual computer; and he would be able to access only what you let him access on the network. There is no hard drive on a thin client, because a thin client is merely a dumb terminal which logs into a remote resource. The computer which is actually running the Warehouse Stock program is locked away in a secure location, and the users could access it only remotely via Citrix which is running on the thin client.

Citrix has tools which can completely manage and lock down this process, so that the user can only do what you let him do, and no more.

I don't know how to set it all up, but that's what we had at my last job.