A read-only user can view all documents and reports but has no access to the calculation or settings.
Go to user management :

Create a user code, assign a password and check Read-only user:

Go to the tab Access to companies and check the companies to which it will be able to access:

The user will therefore only have access to the consultations in the assigned companies. The full menu will be as follows:

The other normal branches of the menu are no longer displayed and available.