Here "bread" refers to food. It does not mean that John never ate food. It means he fasted often, and when he ate, he did not eat good, expensive food. AT: "frequently fasting and not drinking alcohol" or "not eating fancy food and not drinking wine" (See: [[rc://en/ta/man/translate/figs-synecdoche]] and [[rc://en/ta/man/translate/figs-explicit]])
This can be translated as an indirect quote. AT: "they say that he has a demon" or "they accuse him of having a demon" (See: [[rc://en/ta/man/translate/figs-quotations]])
This can be translated as an indirect quote. AT: "they say that he is a gluttonous man and a drunkard ... sinners." or "they accuse him of eating and drinking too much and of being ... sinners." (See: [[rc://en/ta/man/translate/figs-quotations]])
If you translated "The Son of Man" as "I, the Son of man," you can state this as an indirect statement and use the first person. AT: "they say that I am a gluttonous man and a drunkard ... sinners." (See: [[rc://en/ta/man/translate/figs-quotations]] and [[rc://en/ta/man/translate/figs-123person]])