I do both but rarely together, as in I do day hikes, point to point hikes but staying in B&Bs and youth hostels, camping trips but staying in one place, sometimes I do day hikes from the campsite, but I never carrying my tent and all my gear point to point, that is just too heavy and too uncomfortable for me and would spoil my enjoyment of both activities! When I walk I like to travel as light as possible as carrying a heavy pack is tiring and unbalancing and when I camp I like to be comfortable and have all my kit with me, the two are not mutually compatible!
I'd start relatively small on the hiking front with some easy, well signposted day walks starting from home or nearby and build up from there. Komoot is a great app (free!) and will give you loads of suggestions from any point in the country with mileage, estimated time (although I find it a bit over optimistic, I'm not super-slow or unfit but over any remotely difficult terrain I'm slower than it thinks I should be) and difficulty rating. It has built in maps with all footpaths marked on and GPS so provided you are on a well marked route and aren't straying too far from the beaten path you won't necessarily need a paper map. All you need is a waterproof jacket, some sturdy comfortable shoes and something to carry your water bottle and sandwiches in! If you find you enjoy it then there's all sorts you can buy, decent well-fitting walking boots plus walking socks are a good investment and a must if you start to go longer distances, a proper ordinance survey map of the area you are walking in, a compass and the ability to use it is vital if you are going more remote, then there are all sorts of technical clothing, base layers, thermals etc., poles, fancy water systems, lightweight backpacks etc but none of it is absolutely necessary even for more difficult walks so don't go mad before you've decided if you like it or not, it's very possible to enjoy walks without having to go full rambling extreme... if you do find you like it the possibilities in the UK are endless, I'm currently midway through a project to walk the whole pennine way in stages (as I say, staying at b&bs, pubs and youth hostels although people do camp it) but there are absolutely loads of trails up and down the country! The Rambling Man is a great blog/website that I like to browse for inspiration!
Camping, again I'd highly recommend trying it out in a low key way before you make a big investment in lots of gear. Lots of campsites now offer hire of tents and equipment and/or 'glamping' in pods or huts or whatever so you can go for a few nights and see how you find it. I always go for woodland, 'wild style' camping wherever possible as personally being pitched up in a bare field next to loads of caravans or other campers isn't really the back-to-nature experience I am after. A site that allows campfires is also a must for me. A note of caution though, true wild camping (i.e. just pitch up wherever you fancy) is illegal in most of the UK and you do need the landowner's permission to camp. A lot of people either just chance it or go and knock on a farmers door and ask to camp in an empty field for a tenner, (a) I would find this very stressful and (b) although I'm no princess that needs her hair straighteners, somewhere to chill the prosecco and a feather bed to be happy, as a minimum I need basic toileting facilities (compost toilet fine) and a tap for drinking water, neither of which you'll get wild camping. But plenty of smaller, woodland sites do offer the feel of being isolated and in nature while still providing basic facilities. In terms of gear if you do get into it you'll need:
-An easy to assemble tent (personally to sleep 2 adults in comfort and have space to store your stuff I think you'd want a 3-4 man tent minimum)
-Something to sleep on, we have self-inflating air mattresses which are the most popular these days but you can also get light weight, compact camp beds or pump-up air mattresses. Would not recommend just a ground roll although these are the lightest and cheapest option as too uncomfortable/cold for me!
-Sleeping bags of the appropriate tog for the weather, ideally something to use as a pillow too although in extremis you can roll up a jumper as a pillow.
-Some form of stove or gas burner to cook food on, we have a fantastic cast iron dutch oven cooking pot and tripod system to cook food on over the campfire but it is very much not easily portable. If I was trying to point -to- point it I'd take a small collapsible burner and eat out of tins/packets.
-Mess tins or plates or something to eat off, plus cutlery and a water bottle or cup
-Camp chairs (some campsites provide benches but chairs are much more comfortable for evenings around the fire!)
-Headlights for evening dashes to the loo
-Waterproofs, for the inevitable rain, soggy pants while camping is miserable. Plus wellies or other waterproof shoes. And enough layers to stay warm esp in the evenings.
Again there's loads and loads more you can buy, camping carpets and fridges, portable toilets and all sorts but the above would be a minimum basic set up I think...