The Koran is shorter than the New Testament. There’s not a ton of info in it. The rules are a part of the hadiths, which is an extensive commentary on the life of Mohammad, which Islamic scholars use to try to determine orthodoxy.
Muslim women must marry Muslim men. Muslim men can marry Muslims or People of the Book, which in Sunni tradition is Christians or Jews, or in Shia tradtion, Christians, Jews, or Zoroastrians. I don’t believe any Muslims are permitted to marry anybody of non-Abrahamic faiths, although they could still be taken as sex slaves during a jihad.