In which CRM and how is it easiest to organize real-time synchronization with your website catalog?

Question

CMS

There is an e-commerce site. It would be desirable to conduct all work with clients in a separate solution.
2 conditions:
1) Scenario required:
- The customer adds a laptop to the cart and creates an order.
- The manager contacts the client and for some reason it turns out that a mouse for a laptop should also be added to the order.
- To do this, in the interface for editing an order, there should be a button "Add product" and a drop-down list of all products in the catalog.
2) The catalog should be synchronized as close to real time as possible. Catalog size - one million products.
Which solution (open, closed, paid, free, self-hosted, SaaS) is the easiest to adapt to such requests? Where is the simplest API with obvious documentation? How are such tasks solved on such popular solutions as: Bitrix, SalesForce, Megaplan, MySklad, ... ?

Answer 1

that the title does not match the text
any CRM can
do it, of course