There are 3 different things giving traffic information, but I'm basing this on my Mib2 Sat Nav.
In the Sat Nav settings, find and select the Map settings, then look for and select Traffic Flow. There should be options for each of the following ... Freely moving, Slow moving and Stationary. when selected these show borders on the roads in Green, Amber and Red respectively. The coloured borders can be on either side of the road or both, and so indicate which direction(s) of travel are affected. These almost certainly require an internet connection and may require a current Guide & Inform subscription.
The second thing, which requires an internet connection and a current Guide & Inform subscription, is the display of road works and road closures via icons that appear on the map (I think the road closure also displays the affected section of road in Red). If the road works have traffic lights, there will usually be sections of road in Red to indicate queuing traffic. Tapping the road works or road closure icon brings up a side-panel with details, although the location given is often very vague or even wrong so it's better to just zoom in the map and go by the position of the icon.
The third thing is reached via the infotainment menu by selecting Car Net and then selecting Traffic. This displays a map, based on your current location, which shows road works and road closure icons each with an A,B,C... form of label across the area of the map, with a side-panel giving an ordered A,B,C... list showing details of the issues. If you move of zoom the map, the icons and side-panel list are updated accordingly for the new area displayed in the map. Like the above, this also requires an internet connection and a current Guide & Inform subscription.
In addition to the above, there is an option for dynamic route guidance (probably in the Sat Nav Settings->Map but I can't be sure without checking). When this option is selected and you have started route guidance, the route will be altered automatically in real-time to avoid congestion (as indicated by Red or Amber road borders), road closures and accidents. Again, this requires an internet connection and a current Guide & Inform subscription. I can confirm that it works but may come as a surprise when you are directed to follow a new route from what you were expecting.
My assumption is that the Mib3 Sat Nav provides the same features although the method of activation and precise details may differ from the Mib2.