I don't know if this is still true, but it used to be that most Windows laptops didn't have stereo inputs, in case that matters to you.

The rule was that if it has two audio jacks (as most did) they're stereo line output and mono mic input. If they have three audio jacks like a desktop, the third one is a stereo line input.

The solution to that (if you've only got the two and need the stereo input) is to buy an external sound adaptor that plugs into the USB and runs on USB power.

The mono mic input goes to both channels of the sound card. I've never seen a Windows laptop or desktop that has separate mic inputs for each channel.