The water in my kitchen sink was coming out very slow. I looked under neath the sink and turned the main water line. When I went back to check the pressure it was worse. I just about have not water when I turn my sink on.

First thing to check is the aerator. Remove and clean or replace.

I agree with Harold, remove the Aerator turn on the water and see if the water flows good, clean the Aerator and install if the water flow is the same with Aerator removed come back to us, see the Image below