What's happening
ADHD and small jobs can be a strange mix. Changing a lightbulb should take ten minutes. Then it's the wrong fitting, so you look for the right one, then you're reading reviews of smart bulbs, then you're sorting out the drawer the old bulbs live in. Each step makes sense on its own, but nobody decided where the job ended, so it keeps growing until it's eaten the time meant for everything else.
How to get moving
Before you start, write one line saying what done looks like, like "hallway light works". Not "sort the lighting" and not "organise the drawer". Then pick a finish time and set an alarm for that clock time rather than a countdown. "Done by half two" is harder to argue with than a vague "about ten minutes".
When a side job pops up, like "this drawer's a mess" or "should we get smart bulbs?", write it on a later list and go back to your line. If the job can't be finished today because you need a part you haven't got, do the next useful thing, like ordering it or adding it to the shopping list, and call that done for now.
Important tip
Good enough is the finish line for small jobs. Once the light works, stop, even if you can see three ways to make it better. The extras on your later list will still be there tomorrow, and you get to decide whether they're worth a day of their own, instead of drifting into them while the rest of your plans quietly slide.
This is lived-experience content. It is not a promise that a particular idea will work for everybody.