Q.lawn and garden fungus
Starting in mid June, my grass causes severe itching to my feet and legs. By July just sitting on the patio makes me itch and causes a rash on my face and arms. This is happening to other household members too. At the same time, my tomato plant leaves all turn yellow with spots and die. This has been ongoing for many years. Can you help?

I can't address the issue you have with itching but here are links about the plant concerns you have.
https://www.gardeningknowhow.com/lawn-care/lgen/grass-fungus.htm
https://www.gardeningknowhow.com/edible/vegetables/tomato/yellow-tomato-leaves.htm