anyone know how to fix a leaking faucet?

Shut the valves under the sink first and put the plug in the drain so no small parts disappear down it. What you replace depends on the tap. Older two handle ones usually have a rubber washer or a cartridge under each handle. Single lever ones have a cartridge or a ceramic disc. Take the old part to the hardware store and match it, there are dozens that look nearly the same. If it's leaking round the base rather than dripping from the spout, it's normally the O-rings, not the cartridge.