How to simplify the interaction of managers with the site from a technical point of view?

Question

Online shopping

Good afternoon!
I will describe the current situation:
A letter arrives at the post office with an order on the site, the manager enters the letter, looks at the number, calls and processes the order.
Then he marks somewhere with himself and waits for payment, and after payment he gives the printed receipt to the driver.
The system is not clear and debugged. And since everything was built on enthusiasm, they did not see other ways.
How can you build interaction between the client site and the manager?
The opencart system is installed and I would say that it is not very convenient to interact in the admin panel on the orders page.
Maybe there are some services, or plugins?
I would like to see the following:
A person buys a product on the site, the manager sees it either in the admin panel, or in some kind of service.
Processes and the order is attached to it. He sees only his orders, or at least he can sort his own and not attached (new). The manager immediately fills in the data for the client. The delivery date is visible. Perhaps the calendar is built-in to see when which deliveries are scheduled. I would like to see a more modern approach, to simplify the algorithm from ordering goods to its final delivery. To be simple and understandable.
Maybe someone worked or created an online store. How did you solve such problems?

Answer 1

this is called CRM
, you can take any and integrate with existing points,
you can pick Opencart, for example