A paid subscription to Team Forms will not automatically include a subscription to Microsoft Power Automate. Unfortunately, in order to use any third-party triggers and actions (e.g. when a form response is submitted), Microsoft will require the workflow builder to have a premium subscription. This subscription is seperate to your Team Froms subscription.
If you do not have a premium Microsoft Power Automate licencse you may see the following error when saving your workflow:
"This flow was turned off becuase the owner didn't have a premium license"
This error means you need a premium Microsoft Power Automate license and should not be confused with a premium Team Forms license.