how can i bring myself to study?

[u/ilikesushi890]

I’ve always been that kind of person that usually didnt need to study for tests to get good grades because i either paid attention in class or improvised and adapted with past knowledge of what the teacher is expecting me to write or just general knowledge, but now that i have a very important exam coming up this year (med school entrance exam) for which it is impossible for me to learn as i go, i find it very hard to sit down and make myself learn every single thing in that anatomy book. i really want to get in but at the same time i have no motivation. i made a routine, organised my time but i still just cant do it. has anyone ever been in a similar situation? how can i fix this? i also have unmedicated adhd so that could be a reason