He was scourged until skinned, severely enough to kill any other man, then marched several kilometers carrying a huge piece of wood, then crucified while already in shock, and then hung asphyxiating for three hours, in your place, out of completely gratuitous love for you, personally.
How about, just for today, not eating? Out of penance, and respect for Our dying Lord and Savior. Just drink water. Zero food. I promise you won’t die. Jesus died. But you won’t, because not eating for 24 hours isn’t exactly being scourged and crucified.
The traditional fasting discipline for Good Friday (and Ash Wednesday) is a total Fast from food, that is for able-bodied adults to eat absolutely nothing. Nothing.