The Profile is a central piece of the job seeker account. This will be shared with the recruiting company and it important to always keep it up to date.
All information from the account will be fetched to fill up the profile section. Some information will be fetched from GDC records such as the qualification details. The recruiting company will be able to see the documents you uploaded and all other sections apart from Reviews & Ratings - these are private to you.
You can edit the profile details by clicking on the icon of the profile section which will direct you to the Account section to edit the details.