A personal identity of an athlete is an overview of their ‘identity’ documents.
For example: ‘driver’s license’, ‘swimming license’, ‘medical sports checkup’, etc.
It is not a document, but only a list of identities, where you can add a 'valid from' and a 'valid to' date:
A user who has the correct permissions can create new ‘personal identities’, both under “Administration > Personal identities” as in the administrative profile of each athlete.
General info: user functionalities depend on the roles & permissions settings. If a certain functionality does not work within your user account, this will be because you don't have sufficient permissions for this.