ahead, a head

Ahead or ahead ( one word ) means in front of or in advance of, literally or figuratively--
Try to get ahead of that red car.
He finshed the race ahead of everyone else.

To "get ahead" means to succeed--
He spends all of his time and energy trying to get ahead--success means everything to him.

A head or a head ( two words ) means one ( a ) uppermost body part--the part with eyes, mouth, nose, and ears--
We saw a head rise over the fence, followed by the rest of the man. 
It's a modern painting, of a head floating in the air.

A head may also mean a brain, informally--
He has a head on his shoulders--he'll figure it out.

A head may also mean one of the top or chief persons in an organization--
He never dreamed he'd be a head of a department.

A head may also mean one of the striking or prominent ends of a tool or piece of hardware--
Look, a head from an old broken hammer.

Now that you know that, you can say--
"A young man with a head like yours ought to get ahead in no time at all."