What entitlements users receive when they are enabled with Copilot Premium Licenses ?

Our scenario, users with just the Copilot premium license but not with Copilot studio are able to access

https://copilotstudio.microsoft.com/environments and connect to default environment.  The user who has built an agent was able to have a custom built connector active with its agent and started consuming credits ultimately exhausting it. 

The are able to create agents in Agent Builder and copy to Copilot Studio through the setting. How can we disable the same ?

So we are trying to figure if this is the license issue where the moment a user gets enabled with Copilot Premium, they get entitlements to POwer Automate or Power apps.