Welcome to the forum. Your symptoms are indicative of Jock itch
infection ( highly contageous ). It is a fungal infection
caused by Tina cruris. It causes itching, burning,rash and discoloration of the skin. It affects the moist areas of the body like waist, upper thighs, groins, below breast, etc.
It can be treated by miconazole/clotrimazole
oitments when locally applied also work well.
It results due to tight undergarments, obesity, sharing of clothes, sweating, etc. Use anti-bacterial soap, keep such areas dry by putting medicated powder. Wear loose fitting clothes. Take baths 3-4 times a day. wash clothes regularly, treat them with dettol/savlon
You should get clinically examined, you need antifungal medications and anti-biotics ( after consultation with the treating doctor ). Do not neglect, it may spread and cause more discomfort. Take care.