Hello ladies. I haven't given birth yet, but I have a ton of questions…

Hello ladies. I haven't given birth yet, but I have a ton of questions about breastfeeding. I don't understand it all. Should I start breastfeeding right away after giving birth? Do I need to feed from both breasts? If I feed one breast and there's still milk in the other, do I need to express it? How does this even work? How much should I be feeding? Share your experience with those who have already gone through this initial stage ????