Have you camped before? Some of that stuff will be transferable. If not you clearly need to kit your kitchen out - plates, wine glasses etc.
You'll need steps. Something to carry your washing up to the washing up point (we sometimes wash up in the van, sometimes we boot the children over to do it. They are slightly slack washer-uppers though so do sometimes come back with grubbier tea towels then if I had done it...but meh.)
Oh so yes - towels, tea towels, hand towel. We use the thin microfibre towels for showers etc as they dry so much quicker.
If you are planning on using the campsite showers have something to carry you toiletries/towel/clean clothes to the shower block (we use bag for life things )
If you have an awning and are short arses like us maybe a small step stool so you reach the top poles/tie ins - it depends on the awning too.
Chairs for sitting outside with.
Wine.
I have a small hand held hoovery thing
Kettle, tea, coffee, sugar.
Chocolate.
Wine.
If you have to make your bed up from the sofas you may want to get some kind of memory foam topper or some such. As a warning working out how to put a sheet on such a bed is a PITA. You can get special mattress/duvet/caravan specific things. We used to fight with a sheet. Then I got a thin, summer weight cotton duvet and now we use that as our "bottom sheet" iyswim - just lay it out lie on that with another duvet over us. Far, far easier than the sheet fight.
Enjoy.
Will come back if I remember other stuff.