I finished school a long time ago.

I ended up copying lots of notes from people for when I zoned out,
but I really did love that teacher to bits

Helped so much!
In some schools, they'll let you take a test in a separate room if you're known to dissociate
so that there are few distractions and you can concentrate on your test. They do the
same thing for learning disabilities.
Some teachers are good for helping you learn, one thing you can do is take a recorder to
the teacher's desk for during the lecture. Others don't really care.
My schooling was especially hard because it was school where I was abused, and so every time
I enter a school building I fade out.
That doesn't make it impossible though! I still made it through school

I would also go around double checking I got everything I needed to know from fellow students
and the teachers, and I'd keep a list of everything I needed to do, and everywhere I needed to go
throughout the day, so that if I got fuzzy I'd just need to check the list.
It's hard to go through school when you have DID but there are definitely things you can
do to make your courses easier!
Things aren't going to be easy but I have faith in you