Odoo. Restrict user access to edit only one website

Odoo15

In my Odoo instance I have two companies A and B. Company A has website A

Company B has website B

In my system I have user who is worker of company B. He wants to edit website B. He is internal user.

Now he can edit website B. Great. The problem is that this user has also access to website A. I want to restrict this user access only to website B. How to do this?