which is more natural to a Norwegian speaker: "kan du forklare det for meg" or "kan du forklare meg det" ?
They're both common and natural-sounding ways of phrasing the question.
If instead of "det" you were adding an entire phrase (think "...explain how to do X"), the latter would be preferred.
does meg have to come before det? does a pronoun functioning as an indirect object have to come before the direct object like in english? and if thats case, can you do something like Kan du forklare det i meg?
Your options are either "Kan du foklare meg det?" or "Kan du forklare det for* meg?".
*you'll see the preposition "til" used as well, but "for" is the most common, and I'd argue also the most correct choice. "I" is out of the question.
how should "can you explain me that?" be in norwegian?
"Can you explain me that" is not natural English. You explain something to someone, not explain something someone.
But yet i found this translation in this course, so i think it's natural. But a different translation how would sound?
Kan du forklare meg det? would be what you're looking for.
As a native speaker, this actually does work for me. Perhaps sounds a little archaic.
I only ever hear "explain me it" from non-native speakers. Native speakers (where I live) always say "explain it to me".