All the below are different portals for configuring the Power Platform and things associated with the Power Platform. Those who are going to break it down by semantics, yes they all have a different purpose with a lot of overlap.
Last I heard, the ultimate goal is to have everything in the admin center of the Power Platform, Right now I feel like we are playing a game of “Who Moved the Cheese”, as you never know what has changed from the day before!
The biggest confusion is that the options for different features and configurations keep changing on a weekly basis. A month ago, you could go to the Dynamics admin center and add a portal. Fast forward a few weeks and the option is no longer there. Now you need to create the portal through the PowerApps maker portal.
This is just an example of how quickly things are changing without notice. So if you can’t fine it where you found it yesterday, look in one of the Portals listed above..
Yes we get 2 major updates a year but patches are getting pushed every week. Patches used to be very minor but we are finding they are not minor anymore.
Finding the documentation for what has changed is not prevalent either. You can read notes, search websites and read Microsoft documentation and still not have a good understand of what has changed.
We live in the information age, I wish Microsoft would give us this information more readily or give us notice that items will disappear or appear in other portals.