The Caboose at the back of a train was mainly used for shelter for the train drivers and they would sleep in the caboose.
The caboose didn't actually have an engine or anything so it could not be driven.
So the old cabooses were not driven because they could not be driven.
If you're referring to the locomotive that is attached to the back of the trains cars as in one locomotive at front and the one locomotive in back.
That is because the locomotive at back helps to provide braking power to the other train to stop all the other train cars when they are pulling a lot of train cars.
The train engineer in the back of the train in the locomotive can also drive the train as well and help provide additional power to the train in front if the front locomotive is struggling to pull the train cars.
So yes the engineer does drive the train at the back and operates the brakes and even engine when they need additional power to push those train cars forward up a hill etc.