Adesso is more commonly used, especially in Northern Italy. But technically there are differences. Adesso, is for longer periods like centuries, years, Etc. it also represents the past , while going into the present. Where ora, it's mostly for the present only, and for short periods like weeks or or days.
This order is not used in questions, only in positive statements:
- Where do you live now? - ok, affirmative without more detail: "You live now".
- Where do you now live? - strange, but affirmative is OK in: "You now live (here)".
- Where do now you live? - wrong
- Where now do you live? - wrong
- Now, where do you live? - different meaning, like "OK, where do you live?"
Simply duolingo teaches you the best way it can, stop complaining just because it's not comfortable to you, it helped many people and helps many people as well.
If you feel something wrong, research and report it. Crying on the comments will ruin the time of yours and others.
So learn and move on