Hello,
From the symptoms it sounds like ring worm or fungal infections. Wash your skin daily and then dry thoroughly by pat drying,not rubbing. The damp skin is an ideal site for fungi to multiply.Also wear cotton underwears and change them twice a day. and do not share other people’s towels. Most cases of ring worm respond to over-the-counter products, which contain any of several basic ingredients: miconazole, tolnaftate, terbinafine,ketaconazole and clotrimazole.You can consult a pharmacist and get any cream or lotion containing these ingredients. Some of them are Lamisil, Monistat derm, Mycelex, and Nizoral.
If the symptoms persist then pls consult a dermatologist.
Hope it helps.Take care and regards.