Project #47303: Home Improvement

My back door knobs and frame are not functioning properly; they get stuck. I have tried to repair them numerous times, but I'm struggling to get it right. I need someone who understands how to repair them correctly.

Additionally, I have two bedroom doors that need to be screwed in. One frame needs to be properly reinstalled, while the other door just needs to be put back up. I have all the necessary framework for the back door and bedroom doors, but I need help understanding how to ensure they are positioned correctly so that the door knobs work properly once they are installed.