how to get rid of wild toad stools in grass

No easy answer to this one, I'm afraid. Toadstools all over are unusual, they usually occur in rings with a darker area of grass in the centre, and disappear after 2/3 weeks completely. Toadstools are a fungus and therefore have what are known as miccrorhyzal roots (spelling might not be quite accurate here) which are like thin threads which will be spread right through the lawn. Maybe someone else has a solution, but as far as I'm aware, there isn't one.

Hi 3344, Welcome to GOY.
I know you are across the pond, I have had success by lifting the cut on the mower getting the grass longer and applying a solution of Bordeaux mixture in the evening, not in hot sun.
Good luck.

Check out if they are edible. It may be that you have a free gourmet meal on your lawn? Over here St Georges Mushrooms grow this time of year on lawns and are fantastic to eat.

Welcome to GOY from a fellow American. Bamboo is correct in that there really isn't anything you can do for them, but they usually don't last long, so I just ignore them until they dry up. Be very, very careful about identifying any wild mushrooms before eating. There are many native mushrooms in North American that are extremely poisonous.