It's one of the oldest and heaviest questions, no? Honestly, I don't think any short answer does justice to it, especially if the suffering is something you've seen up close.
One verse that helps me think about it: "The One who created death and life for the purpose of distinguishing those among you who would do better." (67:2) To me it says this life is a test, not the final destination, and that what we do with hardship and with each other really matters.
What made you ask? Is it something you've seen, or something you're going through?