How do I leave retail/fast food?

No HS diploma. No college education. I was let go from my dishwashing job almost 2 months ago and haven't been able to net anything. I've applied again to retail and fast food places but was recently rejected from McDonald's for no reason really. I only really have 3 years of customer service under my belt here, and I want to leave asap. I always wanted to do something administrative or even a secretary (that sounds beyond fulfilling to me). Any advice would be greatly appreciated :)