Now the problem is when I speak :(( I looked on Youtube and I don't find best settings....
That's just a case of sound getting to your microphone. Now you're into recording production territory. Look up how voice actors and radio technicians set up their microphones. Since you can't use software to extract your voice, you have to isolate your recording as much as possible.
For a start, try turning down the gain so it doesn't pick up as much from the background. Then move the mic closer to your mouth to compensate. Nicer mics will have a "cardioid" pickup shape that ignores sound from behind the mic, but I can't find any information about whether the Tracer Screamer can do that.
Good luck!