Client/Customer/Contact etc.

Hi,

Can someone explain to me the concept of “customer account” and “contacts” etc.? for a business account please?

When I order (or transfer) a domain name, at one point I arrive at the "Manage contacts/owners" page

The people I create as domain owner/admin/technical, where do I find them later? (to ultimately update their phone number...)

Also where can I designate billing/administrative, technical etc. contacts? for the account/company itself? For the moment it is me who created the company account and it is my name which appears next to the company... Obviously there will be other people involved...
On the phone I was told that I could simply share the credentials of this initial account. This seemed strange to me.

I found this
https://help.ovhcloud.com/csm/fr-account-manage-contacts?id=kb_article_view&sysparm_article=KB0042989

But this does not explain how to generate a new “handle” for other employees of the company.

Thanks.