My apologies, I should have asked rather than assuming you didn't have one. Can I ask whether you have explored whether your difficulties might be due to conditions such as ADHD?

I think this beyond "get motivated" and "consider talking to a therapist/health professional". Honestly, a lot of things that feel like "you just not being good enough" are NOT that-- it's that you literally can not and should not be expected to "figure it out" it without professional help. Good luck OP!