Firstly, are you able to drive up to the point where you will be camping, or will you have to lug your essentials from where you park to where you are camping, and if so, how far?
The answer to this makes a very big difference in how you equip yourself. If you can drive all the way up to where you are camping, then you don’t really have to worry much about weight and volume, so err on the side of caution and throw in the kitchen sink.
OTOH, if you have to lug your stuff, then you have to concern yourself with every ounce you pack. You should really do a couple of easy overnight backpack trips to get a feel for what you really need and what is extraneous.
Here are the basics regardless of camping mode:
Warm clothing, preferable in layers that can be put on and taken off as the conditions change.
Rain poncho
Tent and ground cloth (of course)
Sleeping bag
Sleeping pad (I prefer air mattresses myself, but if you are backpacking the roll up pads are bulkier, but much lighter weight and they strap easily to the pack.
A couple of good water jugs and a good water filter. Or, if you are doing the car thing, a couple of big jugs of city water that you don’t have to sterilize.
First aid kit
A good hank of strong but thin and lightweight rope
A good map of the area where you will be.
Include a signal mirror, whistle, pencil, and paper, and compass in your emergency kit (yes, even you might get lost and need to call attention to yourself)
non-parshable food items like trail mix, jerkey, etc… plus whatever you are planning for regular meals.
Stove (with fuel) and cook ware.
A change of socks (nothing worse than wet socks on the trail…)
Insect replant (depending on the time of year)
Flashlight and extra batteries
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Things to leave behind:
Work
Electronic entertainment devices
Traffic
General stress
You get the idea…