Yes, unlike many other suppliers, the composite boards have the 3D woodgrain effect on both sides of the board. When installed in to your gate, they will look just as good from both sides!
They are simply connected with loose fitting tongue & groove – there is no need for an adhesive between the boards. The frame or bolting method you are using to construct your gates will hold them in position.
Just use a mild detergent and a soft brush to clean down your composite planks. If a more thorough clean is required then a regular household jet washer can be used.