Are there any walk up campsites ?

There are some tent only site's that you would hike to.

Yes

Yes but n ok ne for free will have to pay but real reasonable you will not regret it at all sunsets are beautiful

Yes. But they are at both ends of the park. An they are paid sites. It's worth the money. The other spots are short term. Mostly drop off or pick up your boat.

Not that I seen. Mostly concentrated at either end of the park with wilderness between.