First check that it isn't muted. There might be a sound icon at the bottom, and if you click on that it will show what the sound level is. If it isn't muted, have you tried external USB speakers? If USB and HDMI work then you might have a problem with your onboard speakers. If you can, use windows update or something similar to update the sound drivers in case there's a software error.
If all of that fails, then take it to the shop!
I once had a laptop that could only produce sound when it was connected to an external speaker. It took me close to a month to figure out that it was a small issue with the settings.