Is it possible to study for a lifetime and why?

Of course, it is possible, if it is of some benefit. For example, mastering any kind of activity and applying for making money. As long as a person has a working brain capable of learning and remembering, learning is not only not harmful, but also beneficial for brain activity. Learning is training the brain, just like training muscles, it is able to keep it in good shape and sane right up to old age, if it does not hit a stroke earlier.

If a person needs to learn for something, then he learns, if he is already good, then there is no need to force him.