Hey Derek!
First off, apologies for me taking a while to get back to you.
For your question, the “nav bar” in this context would probably be better listed as the “action bar” or “app bar”. It is indeed that title bar you noticed was missing, and thankfully it’s a simple change to re-add it.
In your values/themes.xml files (both normal and night), you’re using Theme.Material3.DayNight.NoActionBar as your parent theme. This will remove the action bar from the MainActivity that would normally be there. On the plus side, I added it back into your code and your navigation to the Settings screen works perfectly!
Let me know if that works!