I'll just fix the grammar.
"Could you please tell me whether these expressions are correct?"
Your original question sounded as if you were waving your arms and screaming.
1) "If you want to convince an agnostic there is a God, don't give him proof from the Quran. Because he doesn't believe in God, he won't listen to you and you won't convince him."
I'm not sure which side of the argument you are taking here, but anyway...
2) This needs a complete rewrite, and you will have to do it. The sentences are written in such a crass manner that it's actually comical. (Which is also why I'm not sure which side of the argument you're on.)
General advice: if you're learning a new language and struggling with the grammar, avoid any kind of argument. This is for your own sake. Grammar mistakes, poor choices of words, errors in style and so on will completely ruin your credibility. If you want to convince someone, you really can't afford to make mistakes.