When you're befuddled, you're bewildered, confused, lost, or mixed-up. In other words, you don't know what's going on.
A befuddled person is so confused that they just can't understand or figure something out. Or they've had way too much to drink. A difficult math problem could leave you befuddled. If your teacher showed up in a gorilla suit one day, you'd probably be pretty befuddled. Things that are vague and perplexing can also be described as befuddled, like a speech that makes no sense.