Identities are the accounts (sources) you use outside of The Linux Foundation to contribute to a Linux Foundation project. An example would be your GitHub account that you use to submit code to a Linux Foundation project. For more information on how to add or update Identities, visit this page. https://docs.linuxfoundation.org/lfx/my-profile/update-identities
Updating your Affiliations allows you to 'affiliate' your contribution to an organization, or to yourself as an individual, during a specified time frame. If you have added an Identity in the Identities section, you will be able to 'affiliate' it with an organization in the Affiliations section. You can also connect your LinkedIn account in the Connected Accounts section to automatically populate your work history timeline.
You can find more information about your Affiliations at https://docs.linuxfoundation.org/lfx/my-profile/update-affiliations