I have tower casing and my front ports for mic and audio do not work. I'm guessing there must be a wire that I'll have to connect inside the casing to make it work.
Can you direct me to an online illustration of this? A video? Pictures?
You will want to look for a socket on your motherboard like this:
As for helping you to actually wire it... Nearly all new cases have an all in one package where you simply need to line up the guide/missing pin and then it should all be working.
If your case is slightly older where each wire is separate, you will need to consult your manual of either the motherboard (for pin names) or the case manufacturer simply because from experience, I can tell you that they do not always line up or may have alternate names which is a nightmare.