Want to go to grad school but I lack expected coursework
I have never been on an admissions committee and can’t really speak to if it’s actually disqualifying or not. However, even if we operate under the assumption that it is disqualifying that doesn’t mean you can’t go to graduate school, it means you can’t go to graduate school this year. You can enroll as a non-degree student in the university of your choice and take the necessary courses. This may be expensive or difficult depending on the country / situation, but if you really do need the courses it’s an option available to you. I know several people in the US who have done this in math and math-adjacent fields, more commonly for a MS degree but also for a PhD.