Let the adventures begin!
Amazon is your friend. Lots of lists out there on what you need. I would recommend camping iin the driveway if you have a situation that allows for that.
On "hard parts", fresh water line, water filter, pressure regulator, power adapters (just in case), leveling blocks of some sort, wheel chocks, five-way lug wrench and a means of getting a tire off the ground.
Nice to haves include camp area mat, door mats or something to wipe feet on, stuff to do things in or on a camp fire, a broom, chairs, extension cord, coffee maker, electric skillet, outdoor table, outdoor table cloth for campground picnic table, grill and grilling stuff.
We keep a full set of kitchen items in the camper. Plates, cups, silverware, can opener, stuff like that. Think about what you need to prepare basic meals. We have a bin of cooking/food related stuff we keep in the house and take out to the camper before trips. Salt, pepper, cooking spray, oil, stuff like that. We also keep a full set of toiletries in the camper.
There's no end to the stuff you can buy, but you will run out of room if you buy everything. ??
Buy the basics and go from there. I've collected quite a few items that never got used.