How to remover paint from car boot carpet

Possibly depends on the type of paint

If water based, just take the carpet out if possible and hose it down.

Anything else, may be worth doing the same now BEFORE it dries!

Else some carpet stain removers or thinners may work

Let it dry completely then use a wire brush (not a harsh one) to gently disturb & flake the paint. Vacuum & repeat. Second time around I would be tempted to use a wet vacuum.

Then as others have said, get it out & jet wash it. Failing that, go to a scrap yard & get a second hand one in good condition or use a rug. (edited)

This happened to my car many years ago with emulsion paint. No matter how hard I tried to clean the mess it still left a big white stain.

Peel Tec spray can. CT1 Also has a version I've seen in Wickes.
Also there is a product called pretty boy but I'd go with the the spray.

Whatever you use it may effect the original matt colour especially if you leave on too long. I've not had that happen to me yet but what rep told me (edited)

How dod this go ?
I would of jet washed it immediately when it had just happened, im guessing if you let it dry you'll never get it back to normal

Thanks for your suggestions, one thing I learnt from this if paint drops clean or jet wash asap leaving for too long just ruins the carpet as in my case.... gud luck and I wish you must never come across this situation