Use the scroll wheel on the right hand side of the steering wheel. Spin the scroll wheel up and down to select different information. You can have things like Navigation (as you've already noted), Trip computer, fuel consumption, lap timer and a few other items. You can either select the item by scrolling to it and then waiting a few seconds or you can push the scroll wheel in as a button and it will select the item you want. Then you can use the scroll wheel as a button again to scroll through different sub menus. As an example You can select trip computer spinning the wheel. Then you can select between Long term, since refuelling or since start options pushing thew scroll wheel as a button. I hope this makes sense.
Like you I've just bought a Kodiaq only a few weeks back and I'm still learning all about it too. I love it though.