Be aware that Atigun “Pass” is a lousy Aviation route to the north slope, especially if the weather is at all marginal. Anaktuvuk is a MUCH safer pass just to the west. Anaktuvuk is an Inupiat village that sits at the top of a very open pass through the Brooks Range. There’s an airport, an ASOS, a weather camera installation (look up akweathercams), etc. they have a nice little museum there with some interesting stuff.
Galbraith and Umiat are north of Brooks Range, and you may be able to camp there, but the best camping up there is going to be on gravel bars on the various rivers.
As noted, above, take LOTS of bug dope.
Frankly, unless you have some specific reason to go up there, there are lots better areas to explore in my opinion.
Prudhoe is just a big oil field..... The north slope is interesting, and there’s a lot of it, but........weather and bugs.
Brush up on your STOL skills, put some tires on the bus, and there are lots of landing sites.
MTV