How to study with ADHD
Here is what got me through Undergrad:

Sit in the front row, even if you stick out like a sore thumb.
Write down everything the professor says by hand. Don't type it out, just write.
Focus on one subject at a time. If writing a paper, just write that paper for a couple of days.
Turn off your phone. If you don't need a laptop for the class, don't bring it.
A spiral notebook helps you focus more than a binder. Loose pages are the enemy.
Avoid scheduling classes in the evening or around times where you would rather be doing something else.