You're in your 20s with a full time job and still living at home? Fix this immediately.
Honestly it sounds like you need to learn some responsibility. You have a full time job, but you don't like it, so you're going to quit. You have the parents to fall back on.
Maybe a start up will give you responsibility, maybe moving out and financially separating from your parents will give you responsibility. Maybe both with give you double secret responsibility.
I'm actually shocked no one has said this until now. Someone having a full time job but still living with their parents (unless for special circumstances) speaks volumes about their maturity.
Time to start living in the real world. I say jump in and begin your startup. Best case scenario you succeed and end up doing what you love, worst case you took a shot (hopefully one of many) and got out of a job/lifestlye that is making you miserable.