I have a laptop that has a plug for headphones and apparently none for a microphone, but I have a smartphone "headset" that comes with a microphone. How do I get the microphone to work?
Many modern laptops have a headphone / microphone combo plug as you know it from smartphones. Your smartphone headset should simply work on one of these.
It doesn't do it, but I don't know why either, so I ask the question…
Then it is actually just a headphone connection.
You could use your Android smartphone as a webcam with sound on your PC with an app like droidcam, or you can get a cheap USB table microphone.
Is it the headset that came with it? With 3.5 jack connection?