For automatic registration, your organization should be using Intune and Azure Active Directory, and have automatic enrollment of Windows 10 devices set up within Intune using the Azure Active Directory credentials. If that is already set up, then all it requires is that you log in to your HoloLens device using your organizational credentials, and this will automatically trigger the registration of the device on Intune.
Refer to the following article to enable Windows 10 to automatically enroll onto Intune using Azure Active Directory-- https://docs.microsoft.com/en-us/intune/deploy-use/set-up-windows-device-management-with-microsoft-intune#azure-active-directory-enrollment.