By default, all categories of the Supplier are displayed for the Customer. The catalog has the form:

If the Supplier wants to hide certain categories for certain Customers , then he can do this in the administrative panel of the project.
To do this, a user with Administrator rights must go to the project administration panel and go to the Product Categories section .

On the page that opens, a list of the Supplier's Product Categories that are displayed on the portal will be displayed.
You must select the category that you want to hide and click the Change button in the category line.

The page with the category settings will open.
On the category settings page there is a section Hidden

To hide a category, you must select the desired Buyer in the Available Closed to Customers field, transfer this customer to the Selected Closed Customers section, and click the Save button at the bottom of the page.

After saving the settings, this category will no longer be displayed to the selected Customer

Thus, for a specific Customer, you can configure the display of certain categories.
An administrator can hide categories nested in the parent category in the same way.
If the Parent category is hidden, then the child categories will also be hidden.