It's infinitely more difficult with ADHD. I use phone apps to remind myself of everyday things and track my shopping lists. This may sound normal but it's a coping strategy and when it's gone I am unable to function as a normal human being. I cannot go shopping without a shopping list because I will grab things I think I need but that I actually do not need (which is why I have 3 glasses of chocolate spread for bread and 3 packs of cereal, but no bread or milk on most weekdays).
And I will point out that children in Europe are regularly treated for ADHD. I was treated for ADHD. As an adult however, it's impossible to be prescribed ADHD medication (all of which requires a prescription). In a lot of cases, coffee or other stimulants can help but aren't always available and don't fix it all.
Without suffering from ADHD, I'd say it's impossible to even comprehend the mental strain one experiences even for menial everyday tasks like remembering to brush your teeth (I require an app to remind me of doing that when it is not a workday, as my usual routine of going to work and going to bed early for a workday involves it. On weekends or vacation, I do not remember on my own to do basic things like that).