What Is The Cause And Treatment For Penile Infection?

Hello, im 19 years old and I have white cheesy substance on my know and under my for skin and was wondering what could be the cause, I also have red itching little dots on my for skin and its goes red and shiney ive been told its not a sexually transmitted disease but I was just wondering how I could treat it and get it under control because it affects my confidence with getting with girls because they may thing its, an std.. plPlease help