first thing is to determine what sort of paint it is. possibly by the odour, or rub a bit with your finger and see how to clean it off.
if household paint, it will usually be water based (such as emulsion paint for walls, some low-gloss finishes for woodwork) or else oil based (some gloss paints, especially for outdoors)
if water based, start washing it with water and a sponge, with a little detergent. the sooner you start the better, because it hardens with time.
If oil based, start wiping it with white spirit on a rag, using plastic (not rubber) gloves
inside the wheel arch you can use a green nylon scourer with the liquid, or a stiff brush
in both cases, start at once. If it is not fully hardened, the solvent will soften it more and more and you can clean it off. starting last night would have been better
rinse out the sponge in your bucket to keep it clean. change the rag (or use fresh kitchen roll) frequently if using white spirit
the paint looks to be mostly in the plastic wheel protectors, which are quite durable. the painted metalwork can be damaged from vigorous cleaning, so wipe it gently with lots of liquid and try not to rub. this will soften the paint enough that you can wipe it off. it may need buffing and repolishing later.
there are some speciality paints, such as car paint and hammerite, that use special solvents and are very difficult to clean off. you can use thinners or universal solvent if you know what it is.
A body repair shop will be better than a general garage.
@PaintSplatteredVolvo
