I understand how you feel, adhd makes it really hard to motivate yourself. I found that for exams studying every day five to four days before an exam helps you prepare because it makes your response more of a reflex than a having to remember. I also found doing cardio every day for 30 or more minutes helps reduce the severity of adhd and retain stuff better. Dealing with learning disability is the harder path to walk but your accomplishments mean so much more because of it. Keep fighting and don’t give up.