Recommendations for ADHD Software For Students With Forgetfulness and Time Management Issues

I have an intense case of ADHD which my therapist has noted to be quite severe, and they asked me to try and find a good software that would help me keep on track with my syllabus with a calendar system with reminders not miss assignments or exams, and to break tasks down into smaller and manageable pieces. I have experience with software that blocks you from going into other apps/tabs but those have proven to fail for me.

I have downloaded todoist, but I'm not sure if it meets my requirements fully. I am on android and windows. Any recommendations would be greatly appreciated. Thanks.