Inner Thigh Skin Problem (Groin area)

This is for a skin problem on my inner thighs. I have had this issue for around 1–2 months, but it has become significantly worse recently. The skin in the inner-thigh area has become very irritated, raw and painful, especially when my thighs rub against each other while walking. Because of the pain and irritation, I am currently finding it difficult to walk comfortably. The area sometimes feels very sore/burning, and applying products to it can make it uncomfortable. I have attached recent photos for you to examine. Could you please advise what this could be (for example, fungal infection, intertrigo, dermatitis, or another type of infection) and what treatment I should use? I would also like to know how I should clean and protect the area until it heals. Please let me know if I need any oral or topical medication and whether I should avoid any particular creams or products.