To access a Team Subscription License, the user must be created in the portal and then registered to the Team Subscription License.
We recommend that you set up Single Sign-on and User Provisioning so that your end users can automatically be created in the portal.
Team Subscription Licenses are set by default to allow auto-registration. This means that an end user that already has an account in the portal can simply run the software and get registered to the License on the first run. No additional steps are required.
Besides auto-registration, you can use any of the User Subscription License assignment options available for Team Subscription Licenses (for more information, see https://helpdesk.transoftsolutions.com/hc/en-us/articles/360042196694-How-do-I-assign-users-to-my-license-).