There are two ways to use a Mac laptop. One way it would be used to do basic things like web surfing, Email and texting. The other way is the “power user” way. Your MacBook Pro is attached to a 27” (or larger) external monitor. The laptop is in “Closed Display Mode”. If you were thinking about moving up to “Closed Display Mode” with an external monitor and external keyboard, then read this article describing how to set that up.