Oxley Wild Rivers NP

What specifically do you want to do, camp remotely / free camp, what day activities?

You can camp outside the Ebor Pub on the Guy Fawkes river or 400m away at the Showground. You can camp at the Styx River just outside the NE NP or camp in the NP at Thungatti campground (bookings required). You can camp 15km down the Forst Rd at Wattle Flat in the state Forest. Activities?? There's everything from 4 day overnight walks to 1 hour walks.
You can also camp at the adjacent Round Mountain campsite in Cathedral Rock NP or the Native Dog Ck campground in same NP.
If you mean 1/2 day driving trips sightseeing, there isn't much unless you do some of the walks. At 1550m you can see a long way from Point Lookout (in NE NP) on a clear day. There are some tracks through the nearby state forests, have a look at EO Topo/Traveller leading down to the Styx River, they are marked in/on EO Topo.
Be aware the temperatures there will be 10C cooler than Coffs Harbour or Bellingen, and 3-5 cooler than Armidale, which in summer is a good thing. All those places are not locked, you can drive to the front gate of Diamond Flat before you strike the locked gate. You can't go down the mountain on the old Kempsey Rd to Georges Junction whilst the road is under repair, it's meant to be residents only.
West Kunderang is a good place to camp on the Macleay River, it's a private campground within the NP, East Kunderang Homestead is booked out months in advance and is a key job.
It's about 250 000Ha, but heavily dissected by gorges and rivers.
Wollomombi Falls are worth a drive too especially if there's been recent rain.

Around Ebor is some of my favourite camping. Apart from all of the above. For a day trip there is a forest drive north back up to Dalmorton on the Mann river which is pretty. Just dirt tracks, not really a challenge, but there are plenty of side tracks to explore also. Track starts approx 20 km east of Ebor. Well marked on mapping apps.