That people entity is just an example table that they are creating to show how it can be setup for CUD events.
The link to create the new "Virtual Entity Metadata" record for this table is actually buried further deeper within the "New" menu bar (as shown here by navigating the options in the black boxes):
This will pop up a new record where you can enter any name, and link to the entity that you wish to register for CUD events.
Using their example, imagine you've created an entity with the schema name "new_people", when you create a new Virtual Entity Metadata record, you put in any name, but in the Extension Entity Id lookup field enter "new_people" and it should find the virtual entity called Person. For example I've created a virtual entity called "Virtual Invoice" and the schema name could be "new_VirtualInvoice" (Schema name would also be the name field in the example in the original link but this also appears as the "Schema Name" when you view the properties of a table you have already created)
Now I can search for that specific virtual entity as shown below when using the schema name "new_VirtualInvoice" (I've scrubbed out the prefix of the table name in the example below)
