The hardest course to get into at the college where I was a student long ago, was Dante's Inferno -pt.2. You had to have had a foundation knowledge of Italian back in High school, working up through various Italian courses and passing all of them. Finally you get to Dante's Inferno I which was conducted in Italian ONLY. Pass that and you can register for pt.II which is also in Italian ONLY. Fail ANY course and you can forget about II. The sequence of courses would take one's entire college levels. (Up to upper senior.).
I am not good at foreign languages and settled for English. I have 2 books of Dante's Divine Comedy and the Sayers translation is the most analytic.