Google Cloud Identity is included in Workspace. It enables you to create a user and grant them access to other services without having to pay for a Workspace license. It also provides a level of protection to your company - The user will not have access to Workspace resources, such as Gmail, Google Calendar etc. But they will be able to log in as an employee to other resources and you’ll be able to control which services they can use within your organization.
Cloud identity can be used in many scenarios such as for customers and collaborators who don’t need to use company email, it can also be used for testing accounts and for other management tasks.
There are two editions to Google Cloud identity: A free version and a premium version that provides additional features, such as advanced mobile management, advanced password enforcement, automated user provisioning more.
See here for steps to set up Cloud Identity.