Highly recommend watching Russle Barkley's videos about ADHD.
A solution that works wonders for me, after watching Barkley and inspired by "Pact of Punishment" in the game Hades, is to set a penalty for myself.
E.g. for everyday that I don't do a leetcode problem I will pay my partner 50 bucks. Thats a painful enough amount for me.
I must add that this doesn't work for things in future, meaning in 3 months if I don't lose 5lbs I will pay 200 dollars; ADHD brain does not understand time well. Instead it should be planned out and executed in short time periods, daily or shorter. For instance: for every meal that I overindulge I will pay X. For everyday I don't go for a walk I will pay.
This requires integrity and a partner who likes their money ;)