Can Neck, Scalp, Ears And Scrotum Rashes With Itching, Scarring Be Treated?

have been suffering from
1) Rash on the back of my neck, scalp, ears- Its very itchy and powder comes off when scratched
2) Scrotum, anal area is very very itchy and some gray powder comes off when scratched. Its gets worse at nights while sleeping.
3) Bulge and roughness near anal area
4) Some skin protrusion, small kind of hanging extension near anus
5) Rashes on my arms which gets very itchy when exposed to sun
6) Some scars due to itching on my legs below knee

I am really suffering this from many years (some of these) and its kind of gives mental suffering also.

Can you please examine what is this and prescribe some remedy or suggest a good doctor/dermatologist in Bangalore.

Thanks & Regards,
Saajan