the WH bypass/winterizing valves and low point drains are maintenance items so they are not as accessible as water faucet valves.
On your model I suspect you have to remove the drawers below the TV in the bedroom or the drawers & panels below the wardrobe to access the WH valves.
I suspect your FW tank is below the wardrobe as well as the tank drain valve.
Low point drains are usually where the water pump is located, maybe in the wet bay? Look for pull-ring valves to drain the lines.