How can there be a God when there is so much suffering? Great question! Firstly, suffering was never part of God's original plan - the start of Genesis shows us a perfect world going wrong. Secondly, suffering is also not part of God's final plan - the end of Revelation describes a future where there is no more suffering, evil or death. The Bible makes it clear that God is good, so God's nature is not to cause suffering. Much suffering is caused by humans (think about wars, terrorism, inequality and poverty), though not all of it is.
But even if God is not the cause, why does he allow it? Maybe so as not to go against our free will? Perhaps because he can meet us in our suffering? We don't know for definite. Amazingly, though, the God of the Bible never distances himself from suffering. Jesus came to earth and experienced the worst kind of suffering. So we know that Jesus understands our pain, and he promises to be with us through our suffering. Maybe that is more powerful than a one-sentence explanation?