How To Cure Blisters On Face And Body?

Hi , i am a 21 years old guys , i'm 6.33 ft tall and i wheight 90 kgs , i don't eat right at all , i eat pizzas,all kind of fast food , i drink coca cola etc... , the problem i get blisters from time to time on my chin , just 1 and rarely 2 at the same time ,the other parts of my face are ok , except on my foreheads where i have very little blisters , a lot of them , sometimes theye're obvious , but most of the time not , because that area gets irritated easily and becomes red and the blisters then will become obvious , and i have the same blisters on my body , theyre under the skin kinda type.. thanks in advance , and sorry for my english ,i'm not a native speaker .