Im following this website using a different sensor and my output is too low for the GPIO so i don't know whether it effects anything as the program could not work.Can a raspberry pi accept input data if the input voltage is 42 mv when is required is 3.3v?So is it too low that it does not detect any input from the sensor?
To elaborate a little bit and provide a possible solution to the issue - you could use a transistor with the collector attached to the 3v3 outlet of the Pi, the emitter attached to your sensing GPIO and the base attached to your sensor. That way, the sensor will trigger the transistor 'on' with 0.042V, allowing current to flow from the 3v3 to the GPIO and producing the desired result
Are we talking about digital input here? Then, 42 mV don't count as a high.