I go camping at least once a year, I don’t love it but DH and kids do, and I love them so go along 
Here’s my advice to make the most of it, first of all view it as a different holiday, you’ll eat more junk than normal but my kids view that as part of camping. If it makes you feel better, parkdean have very clean toilet/shower blocks so you’ll be ok there.
My top tip- leave the heater on all night and you’ll have a cosy sleep as temps drop so cold at night!
Take dressing gowns and layers for the bed. We have silver mats under our air beds for insulation, the blanket on the air bed as a sheet, sleep in sleeping bags then have a couple of blankets on top (and if it’s cold you can sleep in dressing gown).
Wear welly’s and take them off in the porch area of the tent, but they’re easy for slipping on to take kids to the loos.
Take a washing up bowl with cutlery/tin cups/plastic plates in and always keep these as a camping thing do you don’t have to remember to pack it each year.
Take camping chairs - cheap ones for the kids but spend a bit extra for comfy ones for you and H as it makes the evening much more present- even if it’s raining you can sit in them in the tent.
Torches- aldi do great kids torches that fasten to their heads which making going to the toilet easier at night- or ‘midnight’ walks more exciting!
Food;
Take ready made breakfast foods, like croissants/pancakes/brioche so you don’t have to worry about milk.
Pot noodles (
for snacks/lunches as you only need hot water)
Tinned soups (or cupa soup), easy to heat in one pan.
Get take outs/fish and chips/eat out so you don’t have to faff with too much cooking.
Pack loads of marshmallows, digestive biscuits and skewers- my teens happiest childhood memories are making s’mores every night while camping.
I hope you have a good time...although I will warn you, every time you go, you find more stuff to buy to add to the camping ‘store’, our attic if full of stuff and we still see items used by other people that look great so we buy them for the next camping trip 