It’s not extremely bad for you, some people fast food for x amount of days but our body can be subject to starvation after a day or two without food or water. At that time, the body starts functioning differently to reduce the amount of energy it burns. Eventually, starvation leads to death.
it depends, are u a child? do you work somewhere that requires you to have a lot of energy, are you in school? or are u fasting? if none of those apply to you please go eat before you develop a ED