Thanks for writing to us.
You seem to be having fungal infection
of groin area known as tinea cruris
Treatment requires intake of oral,antifungal like fluconazole along with application of topical antifungal
cream like miconazole or clotrimazole
. If itchy, take tablet cetirizine.
Wear loose cotton clothes. Keep the area dry and ventilated. Apply antifungal dusting powder in morning after bathing to treat the present infection and prevent any further recurrence.
Hope that helped