First of all, you’re not a screwup and everything isn’t your fault. Your brain works differently. Don’t expect the “norm” from yourself. Embrace different.
As I read your post, I wondered if you’re getting any treatment for your ADHD. Without treatment, it’s very hard to improve daily life with ADHD. That could be medication, therapy, healthy lifestyle, coaching…
The first, most important step is to accept and embrace your differences:
ADDitude Community Moderator, Author & Trainer on Parenting ADHD, Mom to teen w/ ADHD, LDs, and autism