God has infinity power and infinity strength. Sure didn't have infinity strength then sure got can build a rock that He can't lift. But since he has infinity power and strength he can do both with ease.
Heaven is where God lives. So if a person doesn't believe him why would God want the person at his place. God accept a persons decision to believe and not believe. Hell is a place where God doesn't exist in other words absence of God.
It's easy to say you're something. It's far more difficult to show through actions that you are. It only requires me to contract my diaphragm in a certain way to make sound in the form of words, proclaiming that I'm a good person. It's far more difficult for me to put my own selfishness beneath God.
They believe in child baptism
Praying to dead saints
Praying to Mary (Jesus mother)
Thinking that they can help you with their prayers.
Catholic also believe that holy communion (bread and wine) turn into body of Christ. Protestant believe it's a symbol not actually body.
Another one is they believe in purgatory.
Also other tradition...
