If you are going to camp, that means carrying a tent, sleeping bag and mat, at least, and maybe stove, fuel, pans, plate/bowl, mug, cutlery, condiments etc as well.
Whilst it is possible to go on camping tours without using a rear rack and panniers, that would generally mean spending considerable sums on lightweight/compact camping gear, and limiting your trip in some way (eg eating out all the time, short duration or summer/fair weather trips).
Your bike doesn't appear to have anything in the way of fittings for a rear rack (which would normally be M5 (bottle cage size) bolts near the rear dropouts and near the top of the seatstays), so that will mean a rack that fits via the wheel QR skewer, and either
p-clips or a
seatpost collar or clamp at the top (the p-clips will be cheaper at a random hardware shop).
Possible racks...
good/expensive:
Tubus Disco (£109)
Cheap:
Axiom Streamline Disc (£35)
I wouldn't expect the cheap one to stand up to prolonged use on rough tracks or last longer than 5 years or so, but for the tryout tour you are planning it will be fine.
Similarly there are a wide range of panniers ranging from expensive to cheap and basic.
Bear in mind that anything that is made from stitched nylon will leak through the stitching holes in wet weather, so you'll want to use un-perforated plastic inside.
There are two general types of fitting for panniers.
The old style is simple hooks at the top, and a length of elastic that runs from the top of the pannier, through a loop on the bottom of the pannier, and hooks onto the bottom of the rack, to stop the pannier swinging out sideways.
The newer style has hooks with clips that go round the top rail of the pannier, and an adjustable bar that slides behind one of the rack legs as you fit the pannier to the rack.
The newer style is worth paying extra for - the old style would sometimes allow the top hooks to jump off the rack if you did something like ride over a sleeping policeman too fast.
On the whole I would counsel against buying gear that's too expensive. If you decide you don't get on with cycle camping at all, you won't have wasted too much money, and even if you do like it, it's best to experiment at the cheaper end of the market. There are many ways to spend on gear that's good, but just not appropriate for the way you like to work.
For example, in the case of panniers, some people don't like the "all in one compartment" aspect of Ortlieb, and would prefer the multi-compartment style of the equally good/expensive Arkel panniers, or for tents, some people like the extra space of a two-person tent, whilst others prefer the reduced weight & bulk of a one-person tent.