"Han har en kjæreste."
Translation:He has a girlfriend.
In order to know if someone means they are in a homosexual relationship how do you ask that
First, you should ask yourself whether you have any reason to ask.
If the answer is yes, you could try "Er du homofil?", "Er du i et homofilt forhold?", or "Er kjæresten din en mann?".
I would never just ask someone without reason to believe do aha. That's rude. But thank you for the response!