Kitchen faucet only gets lukewarm, never gets hot
I would recommend that you start by unscrewing your hot line, of course close the valve first. Then open the valve into a large bucket to make sure you have sufficient pressure and flow and hot water. If everything is good then you probably have a block in the line from the valve to the faucet or you have a bad faucet. Sometimes faucets get plugged or the a lever doesn’t open fully. Good luck.