Question about POS account permission

[anhdd-kuro-159]

I am developing a ticketing system for movie theaters on Shopify.

Currently, I need to address one use case, which is allowing customers to automatically enter their order code of  paid order (or scan a QR code) to print tickets without the assistance of a staff member (you know, like in regular movie theaters).

I am planning to use POS with the idea of creating an account and blocking all access to the store except for a custom app only designed for print tickets . However, I'm encountering some issues:

Issue 1:

Even though I have blocked all permissions, the account can still access order history, products, and place orders. I want to have a tablet dedicated solely to printing tickets.
Is there a way to achieve this using built-in Shopify features like custom apps, POS, etc., or do I have to develop a separate app on Android and iOS and connect it to Shopify through the API?

* I know shopify POS account suppose to be a "Staff" , but I want to allow customer to access some feature of my shop that can directly connect to shop's data and hardware .

Here is what I want to archive , a screen allow input order code and a printer that will print the tickets . Customer can do it themself

Issue 2: Is there a way to control specific app access permissions on POS?

What I mean is, if I have custom-app-1 and custom-app-2 that available on POS, I want specific users to only be able to use custom-app-1.
Currently, I only see permissions to control user access to apps on the Shopify admin and permissions in POS that allow to use all apps those available on POS.