There is no right answer to this question; it depends on your finances, health, travel, doctors you see, what plans are available in your area and many more factors.
At a high level, Medicare Supplement plans offer more flexibility when it comes to which doctors and hospitals you can see, but that usually comes at a cost. You will also have to purchase a stand-alone Part-D drug plan, which adds to the overall cost. Medicare
Advantage plans typically have a network of doctors and hospitals you have to use; if you go outside that network for non-emergency care in many cases, the services will either not be covered or may cost you more.
On the positive side, many Medicare Advantage plans offer significant additional benefits like dental, hearing, vision, transportation, over-the-counter medications, fitness club memberships, and many more.
From a premium standpoint, they can be significantly less expensive (even $0 premium plans are available) than if you had Original Medicare with a Medicare Supplement and stand-alone Part D plan.