I was very tempted to be utterly snarky here, but in the end that doesn't get us anywhere. Can you please describe your problem in some detail? "My headphones don't work" doesn't even give us the slightest clue as to why that might be.
What headphones are they? How are they connected? USB? Front panel audio? Rear audio? Are they connected to a laptop or desktop? If it's a laptop, does it have a single 4-pole combo jack ("TRRS) for both mic and headphones, or separate connectors? Did they use to work, or are you using them for the first time? If you have speakers connected, do you get any sound from them? What operating system are you using? Did you recently mess around with audio settings, or update any drivers? Have you inadvertently changed your audio output device (if you're using a new build of Windows 10, that can be done by clicking the name of the audio output device in the volume adjustment pop-up, and choosing a new one from the list that appears)? For example, if you inadvertently changed it to an unused S/PDIF output your PC has, there's no way anything on your PC would make a sound, unless you changed it back.