Ouch!
Not that long ago this was one of the most difficult repairs a person could be faced with. Not only did it require a lot of fabrication but that fabrication had to be spot on because of the windshield.
But don't despair because recently
THIS PART has become available. Either that or put an ad in Truck Parts Wanted and see if someone can cut that part out of a donor cab.
It's not going to be easy but at least you stand a real good chance of getting it right when it's done if you use replacement parts rather than attempt to fabricate a patch.
LATER EDIT: I just re-read your original post and since you've not done any bodywork before I would STRONGLY suggest you have a pro tackle this for you. No matter how you look at it this is no place for beginners and there is no cheap way out because if it's not done right your windshield will either not fit or leak.
Good luck!
