jackshmo - a human who thinks they're a genius, but in reality, they're

a human who thinks they're a genius, but in reality, they're just a bag of garbage.

My friend is a jackshmo. He tried to build a robot and it just blinked at him.

My brother is a jackshmo. He tried to run a marathon and collapsed after two blocks.

My neighbor is a jackshmo. He tried to plant a garden and now it’s just weeds.