Hi,

Since you want to manage CompanyA and CompanyB separately in Odoo with independent databases, the best approach is to set up two separate Odoo instances, each with its own database.

This is useful when:

    The companies are legally and operationally separate

    You want complete data isolation

    Each company may have different modules, configurations, or users

For further details of Odoo installation, please refer to the following.

* https://www.cybrosys.com/blog/how-to-install-odoo-18-on-ubuntu-24-04-lts-server

* https://www.youtube.com/watch?app=desktop&v=pFNSz8kEqCk

Hope it helps