How to make an admin theme dynamic?


I’m looking for some advice.
My goal is to make an admin theme dynamic, but I really don’t know how. I want to use an admin theme as a “client area”. The client have to log in and get all the information he need (articles, videos, messaging) - less graphs.

Is there any kind of WP Theme out there with the style like an admin theme or do I have to hire a coder to create an own system? Can I connect those themes with a system out there? And if it’s possible, what do I have to search for?