Just take a bunch of stimulants and study leetcode, then go work at microsoft or google. They both have tons of easy boring work at a slow pace with good pay. Theres really no other option
What the hell made you recommend this to someone with ADHD?
With ADHD you want to put yourself in a job thats as hard as possible to get fired from, that still pays well. Some kind of startup that inspires "hyper focus" may work with ADHD in your 20s, but its a ticking time bomb, you will make mistakes. Not being detail oriented, people will come to mistrust you. With a family this is a risky career path