If you are rooted you can use afwall+ to deny internet access for nova
To ensure that the update process finishes without interruption due to weak battery - if that happens it can brick your car. Tbf you can also just connect the battery to a power source and keep the engine off. Depending on update and car updates that take a few hours are not unheard of
Thanks for the suggestions! When you say model, do you mean the OSI model or just an actual network where I can tinker? Lettuce eat lettuce was kind enough to make a list of the basics - I’ll use that as a guideline. Others have provided material as well; it seems I do not need to worry about filling time :)