My favourite job ever was retail. I've worked in three different shops and loved it every time. You need to have at least a slight interest in the product being sold, but that was perfect to me because i had an excuse to find out everything about the new models and explain them to customers. Helping people figure out which one they want out of several options was the best part to me. And there's always something to do so you don't get bored. There are usually set procedures for closing up etc and when you go home you can completely switch off.
Downsides are the pay is crap and there's basically no progression, contracts can be shit and if management is poor, which is common then you'll constantly be getting guilt tripped to work extra hours or shifts.
Graphic design was also fun but you have to train to do it, you can't just start from nothing.
I have taught English abroad, loved that too but I was often flying by the seat of my pants and struggled with the lesson planning. I got into a system with it eventually though.
Interestingly a lot of people with ADHD are emergency workers. I met a gynaecologist at the hospital where I had DS2 who told me she also had ADHD and relished the unpredictable, urgent nature of maternity care. My other friend who probably has ADHD used to work in an ICU. Along these lines I've thought about applying for an emergency call handler job if we come back to the UK. I'm good in a crisis and I think it would be good to be the person getting somebody help and knowing what to do. I don't think I could actually cope with front line danger though so police/ambulance/fire service probably not for me, but those are good jobs to train for if you think you'd enjoy it.
I think the thing I like best is finding out answers and then helping people process that information into a form that works for them.