Yes not eating food can cause fatigue.
Humans need to eat food often enough to provide ourselves with energy and when we don't eat we don't get that energy so we feel fatigued and tired and weak.
When you don't eat your body doesn't get the fuel it needs to provide the body with energy.
Just like when a car has no gasoline the car cannot move.
If you go without eating longer than a few days then your body gets even weaker and after 7 days or so your body basically shuts down and you have no energy at all.
Then when the 7 days comes and you haven't eaten your body is either about to die or you may die then.