Why do you believe Azure Portal is going to be replaced? Azure is the collection of MS cloud services. It isn't going anywhere and there is no name change away from Azure. The portal is unaffected by Entra.
Entra ID is a rename of Azure AD, the underlying domain infrastructure. You only run across Azure AD when you're logging into Azure and managing permissions and whatnot. It is effectively the same infrastructure you probably run on your local work network. There is really nothing to change other than rebranding the AAD login to Entra ID, the rest of Azure is unaffected.