Everyone is scared, but you have quite some time to think of the kind of father you want to be. And believe me, once you see that face, you'll know what to do, and I'm sure you have a lot of help around you. Just think of the kind of father you had, think about what you didn't like about him, and decide what kind of things you will do in the situations you had with him. My best advice, write down your ideals and morals you want to instill in your child, and also write down your bad habits/things you don't want to instill in your child. You can improve yourself, and know where you stand. The baby isn't going to just pop out right now! You have lots of time to figure things out. Read some books to make yourself feel better. And remember, one thing you do will not screw the kid up, you have a whole life time to shape with this child, so you have a lot of time to make their life the best you can.
I know you can do it, good luck, and congratulations!