The Kitchen faucet is a single knob. Both cold and hot has slow water pressure. If you use the sprayer and stop then the water pressure returns to normal for both cold and hot. You must always use the sprayer to get normal water pressure. Sprayer is not part of single faucet but is part of unit.

You have something like junk or dirt in your faucet. You need to first remove the end screen and check to see what's in it. I would let the water run to check the faucet pressure. If it still low, then there may be something other foreign matter in your faucet.

Yep, Roy is on the right track, start with the screen. If that is clean you will have to shut down the main and pull the cartridge. The debris is usually right at the O rings of the cartridge.