Some advice for the OP:
1. Don’t give up working. IMO, a job provides structure to the ADHD and keeps you moving forward instead of spinning your wheels. Change job? Sure. Work 25 hours/week? Sure. Not 0 though.
2. Before you start on the projects, spend some time learning how to design programs. I like HtDP.org but it’s kind of oriented to a class setting.
3. OSSU could be the project of a lifetime. Beware getting sucked in there. That said, some of the courses referenced are excellent. Knowing ALL of them is a lot.
4. Have an exit plan if you are not working. When will you work again? Some bad scenarios are less horrible if you are ready to jump back into the workforce.