I have an electric water heater, it has a black and red wire that needs to hook up to a black, white and bare wire? I know the bare wire screws onto the water heater for the ground the others are the black, white and bare wires they need to hook up to a red, black and white wire so I can get power to the water heater. Help

The black and white I will assume are from a cable, and the red and black are the leads in the water heater. Assuming the cable is a 240 volt feed to a 240 volt water heater, Connect black to black and white to red, and color the white as a ungrounded (live) conductor with a permanent marker at both ends of the cable.