Hi Eric,
An Azure subscription can only be associated with one Entra ID tenant. If an Entra ID user has appropriate permissions (e.g. assigned Tenant Creator role) to their tenant, they can create additional Entra ID tenants. As an aside there are certain cases where you are prevented from creating new tenant even when you have enough permissions, such as if it is a free subscription.
Based on above, you can see that the module text needs to be clarified.
Please click Accept Answer and upvote if the above was helpful. If something is unclear please leave a comment.
Thanks.
-TP