When you cross the US/Canadian border heading INTO Alaska, you will go though the US checkpoint just like any other checkpoint for entry into the USA. You need a current Passport. You will drive about 80 miles (on the Alaska Highway—the ONLY highway) from the border to get to Tetlin Junction—not much more than an intersection. This is where the route from Chicken, Alaska merges with the Alaskan Highway. Just 12 more miles and you will be in Tok.
At Tok (They call it… “The city you always visit twice”), you need to take advantage of the services here and note there aren’t many. I’m a fan of “Fast Eddy’s” where the food is good, plentiful, prices are right, and you can boondock in their parking lot if you ask. This is a busy place right on the highway. There are 2-3 campgrounds here but we thought they were overpriced and somewhat cramped (tight, dusty or muddy driving lanes, and lots of trees and limbs). Tok is a great place to overnight.
Watch for lower-priced fuel (gas and diesel) on the left side JUST as you enter Tok. If you want the cheapest, drive to the main (there’s only one) intersection, compare prices and maybe go back a mile or so to save some bucks.
There is a big gas station at the main intersection that has outside high-pressure hoses you can use to rinse the dirt and dust off your RV—and it will be pretty dirty by then especially if you have gone through any construction. You feed it money and it sprays for a fixed amount of time. It has been excellent every time I have used it. Note that this is not a place to try a thorough cleaning but just an opportunity to blast the chunks of dirt and piles of dust off your rig and engine compartment. Put on some old clothes as some of this dirt will end up on you and you may end up in some mud.
At Tok, you have to make a route decision. You can head south toward Valdez (dead end), west to Anchorage, or you can head north toward Fairbanks. (Not to jump around but think of the highways in this part of Alaska as part of a really crude triangle. You can drive (on good highways for RVs) from Tok to Fairbanks to Anchorage and back to Tok).
I always recommend first-time visitors go to Fairbanks (from Tok), then south to Denali NP, then on into Anchorage. This route covers about all you can easily see/drive in this part of Alaska. Fairbanks is a great “small” city with LOTS of stuff to see. I recommend about a week there.