Does eating once in day slow metabolism
Body goes into starvation mode, it will fight to hold on to fat. You won't lose weight, it's unhealthy, you need food.
It possibly could because it's not good for you.
It will shrink your stomach. It's unhealthy though, I don't recommend it.
Yes,,,you should eat 3 meals a day and 3 snacks a day. I learned that from Jenny Craigs and lost 40 lbs