I just installed a hot water heater and all the faucets have good hot water pressure except the kitchen hot water faucet.is it something I did wrong,and if so how can I correct it.

Hi mir and welcome, you've probably knocked some sediment loose, try cleaning the aerator, there's plenty of knowledge help here so come on back if that doesn't solve the problem. Good luck

I agree with parttime. Sounds like some sediment broke loose and is clogging the hot side of the KS faucet. If pressure is low on hot and cold, sounds like you need to remove and clean or replace the aerator as suggested. If only the hot side is low, you will want to shut off the water to the faucet under the sink and remove the hot cartridge (or single cartridge if single handle faucet) inspect, clean, and flush the faucet body by turning the water on for a few seconds with the cartridge removed (have somebody hold a towel lightly over the valve to minimize mess). Then reinstall the cartridge and see if things didn't improve.