I think I got into my bios somehow, now my computer fan is noisy. Suggestions?

The fan is not dirty. Somehow (and I'm not a techie) somehow while helping a friend walk through a computer problem I notice we are (separately) in the bios or something says bios. I don't know much about bios, other than I'm not smart enough to mess with it. That's all I recall and now my fan continually runs and is noisy. Help?????