After 30 some years of opening and closing my front door, the door knob came off in my hand after exiting and locking the door. This led to climbing through the kitchen window to unlock and open the door. I took the rest of the doorknob off (it was 4 phillips head screws total). I could at least leave the house now, even if I did have a nice round hole in the door. The dead bolt still worked fine. I bought a new lock and dead bolt set, since I only want to use one key for both. I took the old dead bolt off, that was as easy as taking off the doorknob. I have two HUGE full pages of instructions in front of me, but being the savvy nerd that I am, I did a search on google and found this great video showing how to install a doorknob. The most important things to remember are putting the screws on the inside, and making sure you have the catch mechanism in the right direction (it has little arrows or “up” embossed in it).
Here’s the movie, I hope it helps you too!