We are flying into Anchorage 8/10/2020 and flying out 9/1/2020. We plan to rent a class c rv for the trip. We are hoping to see Anchorage, Seward, Valdez, Fairbanks and Denali with points in between. Since we will not have a car how difficult will it be to use the class c for all our transportation? Will we have a problem traveling on any of the roads on this route? Will setting up and unhooking the rv be too much of a problem? Any advice on ways to simplify the trip? Also does this sound like a good itinerary? How important is it to make campground reservations ahead of time? Thanks for any help you can provide.

You will probably need reservations in popular campgrounds such as the one in downtown Seward. Do some research about free camping spots i.e. Guide to Free Camping in Alaska
Setting up sewer and electric connections can be a pain but my husband always did it without complaint. You should probably have some supplies for hand cleaning/wearing gloves when handling the sewer hose. Also decide when and where you are not going to hook up and know ahead of time how long battery and water will last for those times when you camp without hook ups. You will also want to plan meals. Stove and fridge probably operate on propane so no problem there but you will probably need to be careful about water use and have some gallon jugs of water for drinking/cooking.
I am not familiar with road to Valdez. Most roads between towns are highways. You didn't mention Homer which was one of my favorite places. Downtown could be tricky. There's a route to the overlook that includes steep switchbacks I wouldn't try with an RV but you can get to the overlook from the other direction. Our first time out with a pull behind camper, DH made the mistake of parking too close to a supermarket when we got there early to a mostly empty parking lot. Came out to find people parked next to us so it was tricky driving out. Remember to park away from where cars park. At our local NH supermarkets, RVs park at far end of parking lots. If you don't have electric hook up you might have to resort to making coffee on the stove. I cannot cook without a good knife and cutting board so I have taken a few kitchen tools with me when we've traveled.
We did not camp in AK since we were lucky to have some free lodging. There are huge supermarkets in Anchorage and Soldotna but the Seward supermarket was on the small side. No matter where you are, it is nice to be able to pull over and have lunch. With the exception of a local family take-out type of place in Kenai and Moose's Tooth Pizza in Anchorage, I thought restaurants were somewhat mediocre. (Except for passing thru, we didn't stay in Anchorage so probably missed some good restaurants.) You might want to see when local farmers markets are open so you can buy local goods even if it's pastries. I remember someone selling fresh oysters in Homer. When we stayed in campgrounds in lower 48, we used campground bathroom and shower facilities when we could.

We own an RV and spent 4 months in it last summer. Once we got the hang of it, which took about 2 days, setting up was not a problem at all. Basically, you pull in, connect your electrical line to a plug of the same amps, connect your hose to the city water supply and flip the lever, and connect your sewer to the sewer line using a plastic "collar". You may need to raise the sewer line off the ground (depending on geometry) which an expandable "lift". Then we would go inside and find the local channels on the TV (or connect to cable if available) and connect to WiFi (hit and miss on quality) . It takes no more than 10 minutes to set up once you get the hang of it. (we never camped "off the grid" - we were always in full hookup campgrounds).

On leaving the campground, we followed a checklist (after the first time we pulled out with the awning still out). Here's the checklist for vacating the campsite:

TVs strapped down
Cabinets and drawers closed and locked (we have baby latches on ours)
Fans off and vents closed
Bathroom and kitchen supplies put away
Remove privacy shade from front window
Retract awning
Retract slide (you probably won't have a slide in a rental)
Undo and put away sewer hose, water hose and electrical line
Remove leveling blocks if used (we carry a cheap level with us to check whether we need leveling blocks when we first pull in)
Put away barbecue and tools, bikes, chairs, etc.

That procedure takes us about 20 minutes.