The symptoms as mentioned in your post suggest that you might be having fungal infection
in the groin region.
1. Keeping the area dry & avoid too much exposure to water or sweat formation.
2. Antihistamine preparations like cetirizine
to reduce the itching sensation & provide symptomatic relief.
3. Application of topical antifungal
cream to tackle the causative organism.
If symptoms still persist, then it will be better to consult a Dermatologist
& get a proper examination done to find out the actual cause.
So that appropriate management steps could be taken.
Also avoid wearing tight underwear...as it will cause sweating & predispose to fungal infections.
Wishing you a Good Health.
Thanks & take care.