It's also not something you can just "tough out with gritted teeth" because it's fundamentally not something wrong with you, it's essentially society expecting everyone to be able to just deal with what society requires when that's not always possible.
There is hope, and I'd advise talking to a professional if you can, and if not at least research ADHD symptoms and stories about how autistic people finally deal with how difficult life is when you are neurodivergent. It might help you realize that YOU are NOT bad, just different. Short example might be "dogs and cats kind of look and act similarly (both 4 legged mammals with a tail) but only one can easily climb a tree, and it's not a failing of the dog that it can't act like a cat and climb a tree."