Oh, the joys of buying something off the Internet with no datasheet, no part number and no clue how to use it. And then expecting somebody else to tell you how it works.
That module looks like a KY-038, made by Keyes. No guarantees, though, because I'm not telepathic.
Bytes don't "pass through the soundsensor". Bytes don't pass anywhere, in fact. That board has an analogue output,
A0, which is the amplified audio sensed by the microphone. It swings between 0 and 5 volts, and is 2.5V when no sound is being picked up. The board also has a digital output,
D0, which is active-low when the intensity of the sound picked up by the microphone exceeds a thershold. I have no idea what this threshold is or what volume it represents, or if it can be changed.
Have a look at the pages on AnalogRead() for information on how to convert analogue audio to a digital signal.
I don't know what you mean by "a Lib PCM thats converts chars in voices" - 'chars' as in the C-type
chars or do you mean literal 'characters from a voice', i.e. speech recognition? I cannot tell if you have misunderstood something or there's an unfortunate translation coincidence which is confusing matters.