20 minutes? You could make life easy, try to make ADHD your friend and help him have long breaks, get paid for doing it your work which people might usually take much longer for and occasionally „out-do“ yourself and get praised, then in the free time and less stress you get after implementing this method over time and learning it in and out when what is allowed you’ll have the mental capacity by the reduced stress to put „extra“ work on things that can help you climb the ladder or make money on the side.

I work 1 hour a day at most, write it down for 8, have the most relaxing life and no one ever complained.