Our hot water takes forever to heat up and there is no pressure, there is pressure for the cold water what should I do?

Is this an electric or gas hot water heater? If it is a dual element electric heater, you could have one bad element . If it is a gas heater you may have a build up of sludge in the tank and it is keeping the tank from heating properly. And in turn your lines could possibly be plugging up causing the low pressure. Especially if you have galvanized piping. You can hook up a garden hose to the hot water drain valve and flush the tank bottom to get rid of any sludge, and eliminate this potential problem.