Is learning CISCO hard?

Hello, I'm a freshmen in high school and the time to pick electives for next year is nearing. One of my choices is CISCO; however, I am quite unfamiliar with exactly what this is. The only thing I know about it is that it involves computers. Is learning CISCO hard, what would you expect the course to entail, and what how useful would it be in real-life? I find myself to be relatively computer savvy, so I ume I should not have a problem. I'm just looking for other opinions. Thank you in advance.