What would happen if a parent teach unwanted things to thie child and don't teach how to pray,how to read quran etc...
So will the child go to heaven or hell??

The child has the power to decide through their own actions, and they will be guided by something far greater than the parents. The parents have a responsibility to the children, but ultimately they will be judged by their actions, and the children by their own. Everything happens for a reason, by a cause, and in the pursuit of finality. The guidance is given to the child from the Creator, Allah, who will chose to lead or to have mercy on the person. Allah Knows best what is in the hearts of His creation.

"Those who believe in ONE Creator, and who do righteous deeds have no fear of punishment."