Humans exist and live, have meaning, value and will, and the idea of non-self (anatta) only points to the fact that there is no independent essential soul/ego/self that is permanent.
Buddha taught that what we call “I” or “you” is a state consisting of physical and mental components (body, thoughts, consciousness, perception, emotions, etc) – and these components are impermanent.
Everything in a human being exists – a process that is complex and always changing – but nothing is permanent.