Broken bones is a difficult modpack meant to be played in hardcore mode. It has very many mods that could make you die, a lot faster. Your health system is also replaced. Every body part has a certain amount of health. If your body parts lose health you could get debuffs. If your head or body loses all health you die. This could result in death with one shot. Your character can also be weighed down by having too much. You also have too eat very many different foods so make sure to make enough.
Good Luck