Specifically to the OP, in the modern world, it's helpful to know something about religion: the scriptures and history.
In the case of the Quran, there's an additional problem of translation since some parts are vastly different for different translators and other parts are reasonably close.
Also in the case of Islam, there's an additional question of who do you believe when it comes to saying of Muhammad because different groups value different reported sayings differently. (strong vs weak).
Then there's a matter of separating the culture from the religion. Some things are assumed to be part of religion in certain cultures but not others. Islam in the USA, for example, is vastly different than in Saudi Arabia.
In the case of the Quran, there's an additional problem of translation since some parts are vastly different for different translators and other parts are reasonably close.
Also in the case of Islam, there's an additional question of who do you believe when it comes to saying of Muhammad because different groups value different reported sayings differently. (strong vs weak).
Then there's a matter of separating the culture from the religion. Some things are assumed to be part of religion in certain cultures but not others. Islam in the USA, for example, is vastly different than in Saudi Arabia.