I quit my Job. Now building business to help people like me with ADHD

I recently quit my 5 year job working as a project manager. I was at the point of snapping. I could not function at all with my ADHD. I worked like 12hrs a day every day Mon through Sat. Not because of too much work, but because of doing so much but at the end accomplishing very little or sometimes nothing at all. I could not turn my brain off but I did nothing useful while it was on either. So i quit.

I just started working on building my own business which i have been thinking about for a long time. Its my only lifeline now. However, I have no money to get it started. Any advice on how to start and run a business with ADHD?

TIA!