3 day old baby and I am terrified

Today is our first day home from the hospital and I am terrified...I seriously don’t know what to do, I’m so afraid of anything and everything happening to my baby. I honestly had no idea it was going to be this hard, I was naive about it and I just don’t want to do anything wrong. I’ve been pumping because I produced a lot of milk and I’m scared if it’s refrigerated I won’t be warming it enough, we put him in this little seat today and he was so content just sleeping there and I’m afraid it’s bad for him 😭😭 I guess just a rant of a bunch of jumbled thoughts because I’m all over the place. Any tips or advice for a FTM for a newborn?