My hot water pipes froze so I turned on line to free air and open line. When the water unfroze I heard water running in brown and the nothing in the kitchen sink. We now have some water in the kitchen sink but no real pressure . The shower had water after the freeze but the pressure is down too. What to do and where to start?

If there is "brown "crud" in the line, your aerators on the faucet may be plugged. Remove them and clean the screens.

Remove the aerator at the end of the kitchen faucet spout...run water without the aerator in place and then clean the aerator and replace. Hopefully, that gets you up and running again!

Mark