These case studies are controlled information to help you learn how to think critically. You will do the same when you have actual patients. The difference will be that real patients can have all kinds of different problems thrown into the situations. Kind of like mix and match.
Get a good foundation on how you approach the problem solving of these case studies. The process you use (the nursing process) is what is so very important to know. You will hear me refer to it all the time when I am answering care plan questions. These case studies you are doing have answers you can check. In actual practice, there is no answer key for the care plan you develop for each patient.
Here are two lists of links to case studies that were done by nursing students on actual patients that you might want to view:
Nursing News