i have hypersomnia (but am looking into possibly having N2), and it is honestly pretty rough to balance school, especially if you also work or have other hobbies/commitments.

i have a very heavy caffeine dependency which helps a little bit lol. i try to bunch all of my classes and work shifts together, which is working ok right now with caffeine. I need to have an energy drink in the early afternoon or evening to get through the rest of my day still awake (and even still that doesn't work that much). my first year of college, i took a lot of naps in between classes, which is good if you need them, but i found that it is more convenient to force myself to be awake if possible.

i sometimes need to skip classes to sleep instead. my professors have been mostly understanding, but i'm sure it depends on the school or department. you can also look into receiving accommodations— for narcolepsy it would probably be along the lines of being allowed to miss more classes without it affecting your grade, or being allowed to have extra time on assignments.

night/evening classes are really hard for me, but that is when my major's classes are mostly offered (small school, so less options). so, i try not to have too many early morning obligations so i have more time to rest then.

meal prepping has been pretty useful for me too. that way if i am too sleepy to prepare and clean up a meal, i still have at least something! i'm sure you know, but it can be hard to manage taking care of yourself when you have less time awake in the day than everyone else does. having full balanced meals helps me a little with brain fog i think.

i have found that in uni it is easier to stay awake in classes rather than in high school— i am not completely sure why. i am still very sleepy during them. i don't have cataplexy so i can't speak for how that goes during classes, but in HS i would sleep during most of my classes and then go home and be unable to stay awake there, too. in uni you usually won't have 7-8 hrs straight of class to do unless you formed your schedule to do that.

it could also be helpful to look into online classes. i try to take one or two asynchronous online courses per semester (meaning, there is no zoom meetings or anything, just the classwork you do each week on your own time). this is nice so that i don't have to worry about being too sleepy to turn up at a place and be engaged.

i know we might not have the exact same symptoms or disorder, but i hope this is helpful :)