I just bought a new mobile phone. No instruction manual, do not know how to turn on, dial etc. no can use.
As we have a Creator, then He should have left us with an instruction manual.
You have to find the one that makes sense, has universal teachings, no contradictions, agrees with known science, says serve humanity, makes us use our reasoning faculties to think and ponder, says all humans are equal except in what deeds they do etc.