Questions

Hello I am not Christian but have been researching into Orthodox Christianity and one of my friends is orthodox and recommended I ask my questions here. I genuinely am just trying to seek knowledge I do not mean any disrespect at all and I am sorry if I do

1. How do you explain dinosaurs/ animals evolving
2. What are your thoughts on the different denominations of Christianity
3. If God is all powerful why would he become a man to die on the cross to forgive our sins when he could have done it before?
4. What is your explanation of the holy Spirit