Hi
@Tara and welcome to the forum.
A lot of good ideas already given above and no doubt a lot more will be below.......
Maybe if you let us know what size van, number of people in the family, the type of camping you will mainly be doing could help us give some more specific ideas!
You could spend many a dollar to setup the van with extra batteries and solar panels, extra water tank/s etc and only travel and stay in caravan parks. (May not be worth it!)
Then you might add extra 240V power points, a bigger aircon etc and prefer to stay off grid all the time!
Also have a look through the site and see what others have added and see if you need or want things done! Failing that just let us all spend your dollars for you
The main thing is..... When you get it "Get it out there and get it dirty"