I know this is probably the dumbest question ever, however I am a total beginner when it comes to CSS; how do you hyperlink an image on a webpage using an image which is sou
That's really not a CSS thing. You still need your A tag to make that work. (But use CSS to make sure the image border is either removed, or designed to your required spec.)
EDIT: Taking original intent (updated question) into account, a new code sample is below:
You're still in an HTML world for links, as described by other answers on this question.