The exact method you use to run your to do list doesn’t really matter. Some are more helpful than others, but paper and pencil or a whiteboard (or a chalkboard!) can be really just as effective as a fully automated online system.
The number one most important thing you can do to make your to do list effective is… actually looking at your to do list regularly. Make this an unbreakable habit, and not just when you’re adding things through it. I’d guess that three times a day is enough for starters, but more often is even better. You would do well to make it the first thing you look at in the bathroom or on breaks, before you turn to your book or the news or your favourite YouTube shorts.
So there you have it – the sine qua non of to do listing. And yes, I think the habit of looking at the list is more important than putting things on it – if you look at the list regularly, filling it up will happen automatically.