A managed account is an investment account created for you to join the program of a money manager so he can trade on your behalf.
Your managed account portal lets you create a managed account, join a program, and monitor your managed account.
The managed account is not an MT4 trading account, and therefore only appears on your managed account portal.
It is a virtual account, which you connect to the program of the money manager of your choice and can monitor the trades on your account.
You can learn more about navigating your way through your managed account portal here.