How do I remove the hot water faucet that is leaking

A picture would help so we could figure out if this is a valve stem or cartridge. Without knowing that I can at least tell you to shut off the main or the stop under the sink that supplies the faucet. Remove the knob and you should find a threaded collar below the knob that can be unscrewed. Once the collar is off pull straight up on the stem and the valve should come free. Tell us what you have in your hand.