Wait... Do I have ADD? I've never thought so, because I have three close friends who do (diagnosed and medicated), and they've never described it like this. And, like, they're always starting things they don't finish. I have massive trouble starting things, just like you describe, and have built (effective, I'll point out) systems like sibling commenters describe. This whole thread has bent my brain a bit.
I found out I had ADHD because I was catching up with a friend who had been diagnosed since I last saw them. They'd been seeing a psychologist, taking medication, and generally addressing it. They were describing their experiences, strategies they had developed prior and now recognized, and others they were working on with the psychologist for addressing challenges, etc.
I spent the entire conversation essentially going "Wait, what?! That's not normal?" and "Wait, what?! That's a coping strategy, not what everyone has to do to get through their life?".
Called my GP, told them my concern, they referred me to a psychiatrist. Psychiatrist asked me a bunch of questions and was like "Yep, you have ADHD. You have, naturally for someone your age, developed a lot of coping strategies, but those are also consistent with ADHD." and sent me back to the GP to start medication.
So, do you have ADHD? I don't know!
I'd suggest doing some reading about ADHD symptoms, about other people's experiences, and if a lot of it feels really relatable... maybe talk to a medical professional about it. If you do have it, even if you're coping successfully, there's no reason life needs to be as hard as it is.
I had that kind of a revelation right before I started the ball rolling. My kid has ADHD, and I didn’t “get” it for a while. When they described things like you mention, I assumed that was the way it was for everyone. I was completely shocked to find that no, it’s not, or at least not to that degree.
Well, huh.
(Similar story with asthma. I was training for a marathon relay. My doc asked how that was going, and I said it was fine, except you know how after a mile or so, you get cotton mouth and tunnel vision? No. No, they did not know. And that’s how I ended up with a pre-run inhaler, and immediately shaved a minute off my mile pace. Holy crap. Not everyone feels like they’re dying mid-run? Why did no one tell me?)