If there is no self, why do anything?
It essentially doesn't change anything. If you look hard, that "I" was always an illusion. No matter where you try to draw a boundary - it is artificial:


Does the body belong to the self or not? How about that constant flow of matter and energy in and out - at what point does it even belong to the body?
Do thoughts belong to the self or not? You are hopefully aware how much of your thoughts are triggered by others, or even just repeat outside influences. Often they are even rationalizations of what you just did for other reasons.
Do feelings belong to the self or not? Much of these are determined by past experiences, your situation, even medications, weather, food.


So, to keep up this delusion of an "I" separate from the rest of the world requires carefully ignoring all things saying otherwise, which is stressful, even harmful to keep up. If you let that drop away, you'll function as you always did, but with loads of more peace. Don't worry - if this body is hungry it will eat, no matter whether you create such mental complications around that process - or not.