You can invite other users to access your Dynamics 365 CRM (online) instance. Your Office 365 Global admin can do this through the Azure portal. Invited users can access your Dynamics 365 CRM (online) instance using their own login credentials once a Dynamics 365 license and a security role are assigned to them. You don’t need to create a new user ID and temporary password for these invited users in your own Office 365 tenant.
Users can be added into Dynamics 365 through the Azure Active Directory B2B user collaboration. Global Admins and limited admins can use the Azure portal to invite B2B collaboration users to the directory, to any security group or to any application. Admins can use one of the following methods to invite B2B users to their Dynamics 365 instance:
Your invited users can start using your Dynamics 365 instance once a Dynamics 365 license and a security role are assigned to them. For complete instructions, see Invite users to Dynamics 365 with Azure Active Directory B2B.