How to restrict users to a single legal entity/ledger/business unit?

Summary:

I need to restrict users to a single legal entity/ledger/business unit.

Content (required):

Hi,

Could you please help with the setup needed in order to have the users restricted to a single legal entity/ledger/business unit?

We have an external collaborator that should not be allowed to see nor edit the data of the legal entities.

The user should be able only to see (no edit) only the data of a single legal entity.

Thank you,

Teodora

Version (include the version you are using, if applicable):

11.13.22.10.0

Code Snippet (add any code snippets that support your topic, if applicable):