Why did God create us if He knew we were going to sin and cause all this suffering? Wouldn’t it have been better if He never created us in the first place?

First, God did foresee our sin and the suffering we would cause. However, this same foresight allowed Him to see that in order to redeem us (even though we do not deserve it), He would have to become man and be cruelly put to death. So at the same time he saw our suffering, He also saw His own greater suffering and chose to create anyway – even though He enjoyed perfect happiness without us. He loves us that much.