Those questions all have very clear answers.

> Do I need to have my hands on the steering wheel or is the car actually self driving?

You don't need to have your hands on the steering wheel, but you do need to be paying attention to the road.

> Can my Tesla drop me off where I need to be and go park itself?

Not yet.

> And then can I summon it when I'm done?

Yes.

> Can I turn my Tesla into a taxi that picks up other people and earns me money?

Not yet.

> Is it even possible for a Tesla to drive itself unsupervised?

They can (e.g., https://youtu.be/BO1XXRwp3mc), but it's not enabled for consumers yet.